Fermi News

Jun 11, 2022

Happy 14-year birthday, GLAST/Fermi!

On June 11, 2008 (14 years ago) NASA launched the Fermi Gamma-ray Large Area Space Telescope (previously known as GLAST) into orbit. Fermi satellite's name was chosen to honor the famous Italian physicist Enrico Fermi, who first proposed the eponymous mechanism for the acceleration of cosmic rays that creates many of the high-energy gamma rays that the satellite detects. Fermi LAT is continuing to map the entire high-energy gamma-ray sky every ~three hours. Recently the Data-Release 3 of the incremental version of the fourth Fermi LAT catalog of gamma-ray sources (4FGL-DR3) based on the first twelve years of science data in the energy range from 50 MeV to 1 TeV, and containing 6658 sources, has been published. The companion fourth LAT catalog of active galactic nuclei (data release 3, 4LAC-DR3), co-driven by the SSDC Fermi team , includes 1607 new AGN sources relative to the initial 4FGL-DR1 catalog.
The LAT science photon event data archive at the SSDC currently holds more than 1 billion and 530 millions gamma-ray photons ready for science analysis. Finally the 10th International Fermi Symposium will be held in Johannesburg, South Africa, from October 9-15, 2022. Fermi LAT and GMB detectors and instruments were built and are operated by an international collaboration between astrophysicists and particle physicists from the United States, France, Germany, Italy, Japan and Sweden.
Jul 20, 2019

The Moon and SSDC: examples from MATISSE Moon Mapping project and Fermi LAT

July 20, 2019 marked the 50th anniversary of the first humans landing on the Moon on July 20, 1969 as part of NASA's Apollo 11 lunar mission. Such Apollo 11 mission changed our world and ideas of what is possible by successfully landing humans on the surface of the moon, and bringing them home safely, for the first time in history. During the Apollo program of the 1960s and '70s, NASA sent 9 missions to the Moon, and 6 of them landed astronauts safely on the surface, the only times humans have visited another world. A multinational crew of astronauts, including Luca Parmitano of ESA (European Space Agency) at the second time, is arrived at the International Space Station, with a launch from the Baikonur Cosmodrome in Kazakhstan aboard the Soyuz MS-13 spacecraft, in coincidence with this anniversary.

The SSDC activities dedicated to the Moon are mainly those belonging to the "Moon Mapping" research cooperation project, established in 2014 by the Chinese and Italian governments to promote cooperation and exchange between students and scientists from both countries.
The Italian Space Agency (ASI) had the responsibility for the coordination of the Italian side of the project and SSDC played a key role in this assignment, in particular during the operational phase, lasted from 2015 to 2017.
During this period several universities and research institutes carried on joint activities using data acquired by instruments onboard the Chinese lunar exploration missions Chang'e 1 and Chang'e 2, with major focus on data pre-processing, structural and elemental mapping of the Moon and interaction with the solar wind.
The great part of the data have been analyzed and visualized by means of the SSDC tool MATISSE, that allowed to search and map the data directly of the 3D model of the Moon, apart from converting them to 2D formats of widespread use in the scientific community of interest.
The final results of the "Moon Mapping" project will be comprised in a textbook, dedicated to the wide public, whose first draft version has been presented during the "2018 Italy-China Week for the Science, Technology and Innovation" (available here in PDF format).

Another scientific space mission supported by SSDC, the Fermi Gamma-ray Space Telescope Large Area Telescope (LAT) has produced a novel image of our Moon. If we observe the gamma-ray sky above 100 MeV photon energy the Moon is brighter than the Sun! This surprising vision of the Moon produced by the Fermi LAT is represented, for example, in the image representing the integrated photon intensity significance and based on data collected by the first seven years of operation, reported in 2016 also by the APOD web site. The Fermi LAT doesn't distinguish details on the lunar surface, but a gamma-ray glow consistent with the Moon's size and position in the sky is clearly found at the center of the false-color map. The brightest pixels correspond to the most significant detections of lunar gamma-rays.
High-energy charged particles, i.e. cosmic rays, streaming through the Solar System constantly bombard the lunar surface, unprotected by a magnetic field, generating the gamma-ray glow. Because the cosmic rays come from all sides, the gamma-ray Moon is always full and does not go through phases. An updated analysis based on 11-years data is ongoing. The 2016 scientific paper is here. The corresponding INFN news (in Italian) is here.
Jun 11, 2019

Happy 11th birthday Fermi

Today, Tuesday June 11th, The Fermi Gamma-ray Space Telescope is celebrating it's 11th anniversary of launch in orbit. In NASA Fermi social media pages (www.facebook.com/nasafermi/, twitter.com/nasafermi, www.tumblr.com and other) there is a Happy Birthday message, as well as kicking off 11 days of #FermiScience. This starts on Tuesday June 11th and goes until Friday June 21st, 2019. Each day will be a different highlight.
"It has been an incredible 11 years and the excitement continues with new insights and discoveries. Happy Birthday to Fermi!" said Peter Michelson on behalf of the Fermi LAT Collaboration.
Stefano Ciprini (INFN) and Dario Gasparrini (INFN) of the Fermi group at the SSDC join these 11th anniversary greetings, expressing their enthusiasm for the participation to Fermi LAT data analysis and science activities, and thank Peter and all the participants to the Fermi Mission.
Feb 10, 2018Fermi LAT detection of a GeV gamma-ray flare from the distant blazar PKS 0226-559

New ATel posted by the Fermi team at SSDC: ATel #11283
Jan 17, 2018

Fermi GBM wins the 2018 "Bruno Rossi Prize"

We are pleased to report that the 2018 Bruno Rossi Prize of the High Energy Astrophysics Division (HEAD) of the American Astronomical Society has been awarded to Dr. Colleen Wilson-Hodge and the Fermi Gamma-Ray Burst Monitor (GBM) instrument Team for their masterpiece discovery of soft gamma rays coincident with a gravitational wave burst event GW170817 = GRB 170817A in the galaxy NGC 4993  (see also the Oct. 16, 2017 press conference video at NSF, Fermi after minute 21:40) and the confirmation that short gamma-ray bursts are produced by binary neutron-star mergers. This is the sixth time that a space mission supported by SSDC has been directly awarded a Rossi Prize, after BeppoSAX in 1998, Swift in 2007, Fermi (Large Area Telescope, LAT) in 2011, AGILE in 2012 and NuSTAR in 2015. This is also the fourth time that the Fermi mission is awarded with a direct prize to teams of the Fermi instruments (2001 and 2018) or to scientists that have obtained important results thanks to Fermi data (2013 for Fermi LAT gamma-ray pulsar studies, 2014 for the Fermi LAT discovery of the gamma-ray bubbles of our Milky Way galaxy). 
The Italian INFN is an important member of the LAT Collaboration having built the tracker in cooperation with Italian industries, and providing a continuous support to operations and to data calibration, analysis and scientific exploitation. The INFN Fermi team at the SSDC, composed of S. Ciprini and D. Gasparrini, is contributing by establishing and maintaining a mirror archive of the LAT high level data products, by developing quick-look interactive tools and gamma-ray source catalogs and lists, by performing LAT instrument services, shifts, responsibilities, and by participating to gamma-ray data validation, data analysis and scientific exploitation of the LAT archive, this also in the important frame of multi-frequency/multi-messenger astro-particle physics and astronomy.

Read and view more:
Oct 31, 2017Fermi LAT detection of a GeV gamma-ray flare from blazar CGRaBS J0809+5341 (87GB 080551.6+535010)

New ATel posted by the Fermi team at SSDC: ATel #10905
Jul 20, 2017Fermi and Swift discovery of GeV gamma-ray and X-ray emission from the blazar S4 0444+63

New ATel posted by the Fermi team at SSDC: ATel #10584
Feb 06, 2017

Fermi Gamma-ray Space Telescope identified the farthest gamma-ray blazars.

The detection of high-redshift (z>3) blazars by the Fermi Large Area Telescope (LAT) is of great astrophysical importance as they are extreme objects whose energetics remain a mystery.More importantly, high-z blazars tend to host massive black holes and can be used to constrain the space density of heavy black holes in the early Universe. The first detection with the LAT of five gamma-ray emitting blazars beyond z=3.3, has been announced and presented at the American Physical Society meeting in Washington in January 2017, and a paper describing the results has been submitted to The Astrophysical Journal Letters.

Light from the most distant object, NVSS J151002+570243 (z=4.31), began its journey to us when the universe was 1.4 billion years old. These objects have steeply falling gamma-ray spectral energy distributions and, those that have been observed in X-rays, a very hard X-ray spectrum, both typical of powerful blazars.Their Compton dominance (ratio of the inverse Compton to synchrotron peak luminosities) is also very large (> 20). All of these properties place these objects among the most extreme members of the blazar population. The radio-loudness may play a key role in rapid black hole growth in the early Universe. Fermi LAT could have detected just the tip of the iceberg, the first examples of a galaxy population that previously has not been detected in gamma rays

This research was led by researchers at the Clemson University, South Carolina, USA and at the ASI Space Science Data Center (SSDC), Rome, Italy, including D. Gasparrini (ASI SSDC and INFN). They began by searching for the most distant sources in a catalog of 1.4 million quasars, a galaxy class closely related to blazars. Because only the brightest sources can be detected at great cosmic distances, they then eliminated all but the brightest objects at radio wavelengths from the list. With a final sample of about 1,100 objects, the scientists then examined LAT data for all of them, resulting in the detection of five new gamma-ray blazars.

More details in the NASA's press release, ASI news, and in the forthcoming ApJ Letter.
June 14, 2016Fermi Gamma-ray Space Telescope's 8th Birthday

Happy birthday, Fermi! Here below the official message to members and affiliated scientists of the Fermi Large Area Telescope (LAT) Collaboration by the Dr. Peter Michelson, professor of Physics at Stanford University, California, USA and Principal Investigator for the LAT on the Fermi spacecraft.
<<Dear Colleagues, The Fermi Gamma-ray Space Telescope (then known as GLAST) was launched on June 11, 2008 at just past noon (EDT). We should all celebrate the incredible successes of this observatory over the past 8 years. It true has transformed our view of the high-energy Universe and continues to make discoveries about our Universe. Congratulations to all members of the Fermi LAT Collaboration and thank you for your incredible contributions. I am so proud to be a member of such a wonderful collaboration. All the Best, Peter>>.
In these days the gamma-ray mission Fermi, and the other flying NASA missions for the observation of the X-ray sky (Swift, NuSTAR), have received the positive green light to the extension of their mission budget funding and operation lifetime at least to 2018. The NASA has announced this at the end of its evaluation procedure, the Senior Review 2016, on June 9, 2016. The Fermi mission operations have been extended until 2018, with a request to plan for operations through at least 2020. An ASI/INFN/INAF joint public statement is available here.
The ASDC is contributing to the Fermi mission by maintaining a mirror data archive of the LAT high level science data, participating in the data validation, science data analysis, software tools, in the analysis, construction, distribution of the LAT source catalogs. Further activities include the exploitation of the LAT data in connection with multifrequency and multi-mission data, and the contribution to services, duties and coordinations within the LAT experiment.
Apr 29, 2016A novel image of the Moon, based on data collected by the Fermi Gamma-ray Space Telescope's Large Area Telescope (LAT) instrument during its first seven years of operation (2008-2015)



If you could only see gamma-rays, photons with up to a billion or more times the energy of visible light, the Moon would be brighter than the Sun! That startling notion underlies this novel image of the Moon, based on data collected by the Fermi Gamma-ray Space Telescope's Large Area Telescope (LAT) instrument during its first seven years of operation (2008-2015). Fermi's gamma-ray vision doesn't distinguish details on the lunar surface, but a gamma-ray glow consistent with the Moon's size and position is clearly found at the center of the false color map. The brightest pixels correspond to the most significant detections of lunar gamma-rays. Why is the gamma-ray Moon so bright? High-energy charged particles streaming through the Solar System known as cosmic rays constantly bombard the lunar surface, unprotected by a magnetic field, generating the gamma-ray glow. Because the cosmic rays come from all sides, the gamma-ray Moon is always full and does not go through phases. The first gamma-ray image of the Moon was captured by the EGRET instrument onboard the Compton Gamma-ray Observatory, launched 25 years ago.
Nov 20, 2015

Multiwavelength evidence for quasi-periodic modulation in the gamma-ray blazar PG 1553+113

Italian scientists using about 7 years of data from NASA's Fermi Gamma-ray Large Area Telescope (LAT) have detected the first evidence of quasi-periodic changes in the gamma-ray flux emitted by the BL Lac object PG 1553+113. PG 1553+113 lies in the direction of the constellation Serpens Caput, with a redshift lying between 0.395 and 0.6. This optical/X-ray-selected blazar is intensively observed from Cherenkov telescopes at very-high energy gamma rays and may have associated PeV neutrino emission, potentially increasing the interest for this result.

If confirmed in the next years, the discovery would mark the first years-long cyclic gamma-ray and correlated multifrequency emission ever detected from any AGN, providing new insights into physical processes near the central supermassive black hole.

This research is led by S. Ciprini and S. Cutini two INFN researchers belonging the Fermi team at the ASI Science Data Center (ASDC) in strict cooperation with A. Stamerra, INAF Senior Scientist at ASDC. The work has seen also a synergetic international collaboration with scientists like S. Larsson (Royal Institute of Technology, Stockholm Sweden), R. Corbet (NASA Goddard Space Flight Center, USA), both periodical visitors and collaborators of the ASDC, D. Thompson (NASA Goddard Space Flight Center, USA and Deputy Project Scientist of the Fermi mission), W. Max-Moerbeck (National Radio Astronomy Observatory, Socorro, USA) and M. Perri (INAF Rome and ASDC).

Motivated by the possibility of regular gamma-ray changes, the researchers examined a decade of multiwavelength data. These included long-term optical observations from Tuorla Observatory program in Finland, Lick Observatory, KAIT observatory in USA, and the Catalina Sky Survey near Tucson, Arizona, as well as optical and X-ray data from Swift XRT and UVOT instruments and radio, 15 GHz, data from the Owens Valley Radio Observatory, USA. Ciprini, Cutini, Stamerra and their collaborators published the findings in the Nov. 10 edition of The Astrophysical Journal Letters.

The indication of a possible 2-year periodic modulation was possible thanks to the continuous all-sky survey of Fermi; the increased capability of the new Fermi LAT Pass 8 data; and the long-term radio/optical monitoring of LAT gamma-ray blazars. If the gamma-ray cycle of PG 1553+113 is in fact real, the blazar will peak again in 2017 and 2019, well within Fermi's expected operational lifetime.

The scientists identified several scenarios that could drive periodic emission, including different mechanisms that could produce a years-long wobble in the jet of high-energy particles emanating from the black hole. For example pulsational accretion flow instabilities, jet precession, rotation and/or helical structure, or mechanisms analogous to low-frequency QPO of high-mass binary stars. The most exciting scenario involves the presence of a second supermassive black hole closely orbiting at milliparsec scales the one producing the jet we observe. The gravitational pull of the neighboring black hole would periodically tilt the inner part of its companion's accretion disk, where gas falling toward the black hole accumulates and heats up. The result would be a slow oscillation of the jet much like that of a lawn sprinkler, which could produce the cyclic gamma-ray changes we observe.

In this rather less probable but exciting scenario very-low frequency gravitational wave emission would make PG 1553+113 an ideal multimessenger high-energy-photon/neutrino/gravitational-waves source, in this sense the blazars could represent the major "cost-free" accelerators in the nature and ideal multifrequency and multimessenger physics laboratories.


Fermi observations suggest possible years-long cyclic changes in gamma-ray emission from the blazar PG 1553+113.
The marginal significance of the 2.18+/-0.08 year period gamma-ray cycle is strengthened by correlated oscillations observed in radio and optical fluxes.
The first, top panel, shows Fermi Large Area Telescope data from August 2008 to July 2015 for gamma rays with energies above 100 million electron volts (MeV) with one possible explanation for the gamma-ray cycle, an oscillation of the jet produced by the gravitational pull of a second massive black hole, seen at top left in background in this artist's rendering [credits: NASA's Goddard Space Flight Center/CI Lab].
The panels following below the pictorial artist's rendering show all the data used in this research. From top to bottom the gamma-ray (E>100 MeV, and at E>1 GeV) flux light curves (the second, third and fourth panel), the X-ray (0.3-2.0 keV) integral flux by Swift XRT, the optical flux density (R filter) from Tuorla, Catalina CSS and KAIT monitoring programs and Swift UVOT, where the dotted line is the gamma-ray light curve scaled and superposed, and the 15 GHz flux density from the OVRO 40 m radio telescope and by VLBA (the fifth, sixth and seventh panel).
Jan 21, 2014Fermi-LAT Detection of Delayed Gamma-ray Flares from Gravitational Lens B0218+357

Using data from the Fermi Large Area Telescope (LAT) scientists of the LAT Collaboration, including staff of ASDC, have discovered the first gamma-ray signature of a delay between flares from the gravitationally lensed images of a high-energy emitting blazar. The time delay was observed in LAT flux light curves of blazar S3 0218+35 (OD 330, B2 0218+35, 2FGL J0221.0+3555), a known double-image system as lens B0218+357 (2014 ApJL, accepted, arXiv:1401.0548). Long before light from B0218+357 reaches us, it passes directly through a face-on spiral galaxy, about 4 billion light-years away. The galaxy's gravity bends the light into different paths producing dual images of the background blazar. The B0218+357 lens images hold the record for the smallest separation of any lensed system known. While radio and optical telescopes can resolve and monitor the individual blazar images, Fermi's LAT cannot, but can, instead, observe a "delayed playback" effect. Three episodes of flares showed playback delays of 11.5 days.

This accomplishment opens new avenues for research, including a novel way to probe emission regions near supermassive black holes, and multi-messenger opportunities triggered by observed gamma-ray flares and the Fermi LAT continuous sky monitor. Time-dependent searches for neutrino signals from flaring blazars seen by Fermi LAT, for example, are of interest of experiments like IceCube, ANTARES, KM3NeT. Lensed gamma-ray/neutrino blazars, in particular, might lead to neutrino quantum interference signals as the lens could act like a cosmic beam splitter, as noted by S. Ciprini (ASDC) when he discovered the first gamma-ray flare from this lens (Aug. 26, 2012, ATel#4343), and collaborator of this first study.

C.C. Cheung (NASA GSFC) and S. Larsson (Stockholm Univ. and ASDC visitor) coordinated the LAT study of lens B0218+357, thanks also to a granted target-of-opportunity pointed observation of the LAT (Sept. 24 to Oct. 1, 2012) triggered by the observation of a second flare (ATel#4361). Intriguingly, the gamma-ray delay is about a day longer than radio observations report for this system. And while the flares and their playback show similar gamma-ray brightness, in radio wavelengths one blazar image is about four times brighter than the other. Gamma-rays should arise from different regions with respect to radio-band flux, so these emissions likely take slightly different paths, with correspondingly different delays and amplifications, as they travel through the lens.

As long as the Fermi LAT all-sky survey is continuing it may even be possible to find other high-energy gravitational lenses, even if the gamma-ray lensing signal cannot be easy to disentangle, as emerged from a first study, lead by ASDC and the Padova Fermi group, on the other strong Fermi LAT lens known, blazar PKS 1830-211 (ATel #2943; ATel #4158; ApJ paper submitted by the LAT Coll.; 2011, A&A, 528, 3; and 2013 A&A, 558, 123).





Further links:
Jun 13, 2013

Happy Fifth Birthday to Fermi. Five spectacular years in orbit!

From the Fermi LAT Project Scientist Julie McEnery:
"June 11, 2013 and 5 years since the launch of of GLAST, which was renamed Fermi shortly afterward. It has been a spectacular success and incredible journey across the high-energy Universe with Fermi.
In the past five years, 1130 refereed papers have used Fermi data or results, with a cumulative 26038 citations. The three most-cited are the LAT instrument paper, the first electron spectrum paper, and the first LAT source catalog. In addition to writing lots of papers, we are using Fermi data to produce important, high impact papers. Ranked by citation count in astrophysics, Fermi papers (sometimes several) are in the top 10 in 2009, 2010, and 2012. Fermi results are clearly having a significant impact.

Many of these published results are made possible with data (and the work of scientists) from different wavebands. Among many examples, the Pulsar Search Consortium has timed over 700 pulsars in support of Fermi. Swift has followed up with X-ray and UV observations of hundreds of LAT flaring sources and dozens of LAT GRBs. Hundreds of Fermi-LAT sources are monitored in radio, X-ray and optical wavebands (see http://fermi.gsfc.nasa.gov/ssc/observations/multi/programs.html).

These results have been widely disseminated to the public. In addition to many press releases by university and international partners, NASA has supported 5 media telecons, 22 press releases and 15 features. These stories have been accompanied by 39 videos and supporting animations, which have had enthusiastic reception. In 2012 alone, the first year for which we have a report from the NASA Goddard Scientific Visualization Services server, Fermi videos exceeded 3.4 million views, with many, many more views via YouTube.
Among the most popular are:
Einstein's Cosmic Speed Limit: http://svs.gsfc.nasa.gov/vis/a010000/a010500/a010510/index.html
Terrestrial Gamma-ray Flashes Create Antimatter,
http://www.youtube.com/watch?v=lXKt7UVjd-I&list=PL9900C9C6BBDA9551&ind
Fermi discovers giant gamma-ray bubbles in the Milky Way
http://svs.gsfc.nasa.gov/vis/a010000/a010600/a010688/index.html

The spectacular work with Fermi has been noted by our peers in the science community. Scientists working with Fermi, and the Fermi Large Area Telescope team have received several prominent awards: the Bruno Rossi prize (twice), the Warner prize, the Panofsky prize and the Duggal Prize (also twice).
The LAT stands on the eve of 300 billion LAT event triggers (299,864,708,616 as of 15:13 UTC today). The LAT Instrument Science Operations Center (ISOC) have used 1200 CPU-years to process over 2 PB of data; an additional 1700 CPU-years have been devoted to Monte Carlo simulations to support understanding of the performance of the LAT and the LAT data. The ISOC has sent 1,789,794,674 events to the FSSC of which 268,324,179 are in the photon database (the remainder are in the extended database).

The Fermi Science Support Center (FSSC) at GSFC have served about 20 TB of LAT data for a total of 159,879 queries, in addition to a large number of direct downloads of the weekly data files. For the GBM, over 67 TB of data have been downloaded by the GRB and Solar communities. In addition to serving data, the FSSC have worked to ensure that people are able to fully use them. The FSSC have answered over 2400 requests to the Fermi Helpdesk and participated in 23 analysis workshops and schools in 15 different institutions in 11 cities and 3 countries. This is a lower limit thanks to additional externally-hosted workshops run by instrument team members.

Participation in Fermi by the scientific community has steadily grown since launch. To date, 1269 individual guest investigators have participated in the six cycles of the Fermi Guest Investigator program. This is a lower limit on the number of scientists using Fermi data, as many additional people are supported by agencies in other countries. Fermi of course has made lots and lots of observations. While collecting high quality science data, the spacecraft has spent 96% of its observing time in survey mode, 3% in pointed mode, and the remainder in maneuver mode. Fermi has made over 90 autonomous repoints, 31 nadir observations and 12 targeted observations at 8 objects (3 with modified rocking: PSR B1259, the Sun, and Mrk 421; and 9 pointed mode observations: Sun, Crab nebula, Cyg X-3, 3C 454.3, Galactic Center, and S3 0218+35).

The GBM have triggered onboard on 1151 GRB, 370 TGF, 522 solar flares and 192 magnetar outbursts. Many additional gamma-ray transients have been found in searches of the downlinked data, especially after we transitioned to routinely collecting higher time-resolution GBM data in July 2010.
The LAT monitored source list now numbers 105 sources, with publicly-available lightcurves for each. The LAT Flare Advocates have written 207 Fermi-sky blog entries (http://fermisky.blogspot.com/), and written 239 LAT ATels (https://www-glast.stanford.edu/cgi-bin/pub_rapid/) since July 24, 2008.
Not to be outdone on the communications front, the Flight Operations Team have generated over 3000 presentations for weekly and quarterly status meetings and the ISOC have written many weekly entries in the LAT diary. Most importantly, over 100 students have written a thesis based on Fermi data.
It's also important to continue to have a functioning observatory to work with, to that end in the 27537 orbits of Fermi the Fermi observatory the FOT have sent 10206 commands to the observatory and scheduled 18877 KU contacts to downlink the science data. We have had one collision avoidance maneuver (successful!), and one successful mission extension, hopefully the first of many.

Starting the sixth year of the Fermi mission, the spacecraft and instruments are continuing to work well, the scientific output from the mission is continuing to increase. We cannot predict the discoveries to come, but we can look forward to them."

All of the achievements have been made possible by the hard work of a worldwide Fermi community and with the support of the National Aeronautics and Space Administration (NASA) and the Department of Energy (DoE) in United States and agencies in France, Germany, Italy, Japan, and Sweden. The Fermi LAT collaboration in particular is supported in both the development and the operation of the LAT as well as scientific data analysis by NASA and DoeE in USA, the Commissariat à l'Energie Atomique and the Centre National de la Recherche Scientifique / Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana (ASI) and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K.A. Wallenberg Foundation, the Swedish Research Council and the Swedish National Space Board in Sweden. Additional support for science analysis during the operations phase is gratefully acknowledged from the Istituto Nazionale di Astrofisica (INAF) in Italy and the Centre National d' 'Etudes Spatiales in France.

The ASI Science Data Center (ASDC) is contributing to the Fermi mission by maintaining a mirror archive of the LAT high-level science data, now loaded with Pass7 class events and holding about 268 million of gamma-ray photons collected between August 4, 2008 and June 11, 2013. ASDC is contributing to the Fermi mission in development of quick-look analysis software, interactive data exploration and analysis interfaces through online web tools, software support for publication and maintaining of gamma-ray source catalogs and LAT science data distribution, and providing support to users for data reduction methods and analysis. The Fermi team at ASDC is involved in technical and science activities within AGN, GRB, and Catalogs LAT science groups, participating in LAT catalog releases, source identification analysis, in exploitation of LAT data in connection to multi-mission archives also collecting and analyzing multifrequency data, and performing source population studies, and spectral and temporal variability analysis. The participation to the distinct LAT instrument and science duty service shifts, the set of new international collaborations and the communication of analysis result, the support in organization of events and conferences and public outreach activities are also tasks of the Fermi team at ASDC.



Links:

Fermi ASDC site:
http://fermi.asdc.asi.it

Fermi ASI page:
http://www.asi.it/en/activity/high_energy/glastfermi
http://www.asi.it/it/attivita/astrofisica/fermiglast

Fermi NASA official site:
http://fermi.gsfc.nasa.gov/

Fermi Science Support Center (FSSC) site:
http://fermi.gsfc.nasa.gov/ssc/

Fermi NASA mission site:
http://www.nasa.gov/fermi/

Fermi Large Area Telescope (LAT) instrument and collaboration page:
http://www-glast.stanford.edu/

Fermi Gamma-ray Burst Monitor (GBM) instrument and collaboration page:
http://gammaray.msfc.nasa.gov/gbm/

Fermi Education and Public Outreach site:
http://fermi.sonoma.edu/

Fermi LAT Instrument Science Operations Center (ISOC):
http://glast-isoc.slac.stanford.edu

Fermi LAT project site:
http://www-glast.slac.stanford.edu/
Apr 30, 2013GRB 130427A: high energy gamma-ray detection by AGILE and Fermi

AGILE detected high energy emission above 50 MeV with the Gamma-Ray Imaging Detector (GRID) and above 350 keV with the Mini-Calorimeter MCAL) from the long-duration GRB 130427A on April 27, localised by Swift (GCN 14448, Maselli et al.).
Due to the exceptionally high fluence above 100 MeV of this burst, it was possible for the first time to derive its properties using the technique ("maximum likelihood") routinely used in the standard data analysis of AGILE-GRID point sources.

This burst was detected above 100 MeV and reported previously by the Fermi Large Area Telescope (LAT).
The LAT data show a multi-peaked light curve consistent with the Fermi GBM trigger. More than 200 photons above 100 MeV are observed within 100 seconds with a TS above 1000.

Different observations by other space missions such as MAXI, INTEGRAL and Konus-Wind and by optical/NIR and radio ground-based telescopes followed.

Some GCN issued:
Swift localization: GCN# 14448 (Maselli et al.);
MAXI-GSC detection: GCN# 14462 (Kawamuro et al.);
Fermi-LAT detection: GCN# 14471 (Zhu et al.) and http://fermisky.blogspot.it;
Fermi-GBM detection: GCN# 14473 (von Kienlin et al.);
INTEGRAL-SPI detection: GCN# 14484 (Pozanenko et al.);
Fermi-LAT refined analysis: GCN# 14508 (Zhu et al.).
AGILE detection: GCN# 14515 (Verrecchia et al.).
Mar 05, 2013Significant increase in the gamma-ray emission from the Crab Nebula region reported by Fermi and AGILE satellites

A new increase of the gamma-ray activity above 100 MeV from the Crab Nebula has been recently reported by Fermi-LAT (ATel #4855) and AGILE-GRID (ATel #4856). On March 3, the daily-averaged gamma-ray flux was about a factor of 3 greater than the source average flux in the second Fermi LAT catalog.

Fermi has interrupted the all-sky scanning mode on March 4 starting at 15:30 UTC to observe the Crab Nebula and is expected to remain in this observing mode for up to 300 ks, depending on when the flare fades.

New ATel issued: Fermi LAT detection of a new gamma-ray flare from the Crab Nebula region, ATel #4855 (R. Ojha et al.)

New ATel issued: Enhanced gamma-ray emission from the Crab Nebula region detected by AGILE, ATel #4856 (E. Striani et al.)
Feb 15, 2013

Fermi Gamma-ray Space Telescope Proves Supernova Remnants Produce Cosmic Rays Through Detection of the Characteristic Pion-Decay Signature

The Fermi Large Area Telescope (LAT) detected the characteristic pion-decay feature in the gamma-ray spectra of two supernova remnants (SNRs), IC 443 and W44. This detection provides direct evidence that cosmic-ray protons are accelerated in SNRs. Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects was still lacking. When accelerated protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma rays. This offers a compelling way to detect the acceleration sites of protons.
The identification of pion-decay gamma rays has been difficult until now because high-energy electrons also produce gamma rays via bremsstrahlung and inverse Compton scattering.
The first clear-cut evidence the expanding debris of exploded stars produces some of the fastest-moving matter in the universe is revealed by observations of Fermi LAT.
This discovery is a major step toward understanding the origin of cosmic rays, one of Fermi's primary mission goals.
The Fermi discovery builds on the previous discovery of neutral pion decay in W44 observed by the Italian Space Agency's AGILE gamma ray observatory and published in late 2011.

Read more:

- NASA Top Story
- SLAC Press release
- The paper of the discovery on Science
- Media INAF press release
Jan 22, 2013

Fermi LAT detection of renewed gamma-ray flaring activity from the radio galaxy NGC 1275 (Perseus A, 3C 84)

New and interesting ATel issued: ATel#4753 (S. Ciprini).
Fermi LAT has observed GeV gamma-ray flaring activity from a source positionally consistent with NGC 1275 (also known as Perseus A, 3C 84, and 2FGL J0319.8+4130) a radio galaxy located at the center of the Perseus galaxy cluster. On 2013 January 20, NGC 1275 was in a high state with an average daily gamma-ray flux (E>100MeV) of (1.1+/-0.3) x 10^-6 photons cm^-2 s^-1 (error statistical only).
Fermi already observed increased GeV activity from this blazar in 2010 July (ATel#2737). Thanks to this very high energy gamma-ray emission was discovered by the MAGIC imaging air Cherenkov telescopes (ATel#2916).
The current renewed activity is characterized by a GeV flux significantly larger than the past flares. NGC 1275 has been in a relatively high gamma-ray state in the last months and now the GeV flux observed is reaching the highest historical value observed for the source.
TeV-Cherenkov and radioastronomy communities are highly interested in the gamma-ray flaring activity of this nearby radio galaxy.
Jan 15, 2013

Fermi and VLBA observe blazar's gamma-ray flares erupted far from its black hole

In 2011, a months-long blast of gamma-ray energy (E>100MeV) launched by an enormous black hole in the blazar 4C +71.07 (S5 0836+71, z=2.172) 10.6 billion years ago swept past Earth.
The correspondence between the re-weakening of the gamma-ray activity measured by the NASA's Fermi Gamma-ray Space Telescope, and the radio phenomenology observed by the ground with the Very Long Baseline Array (VLBA) of radiotelescopes is spectacular. 4C +71.07, placed in the Ursa Major constellation, was discovered as a source of strong radio emission in the 1960s.
In early November 2011, at the height of the outburst, this blazar was more than 10000 times brighter in gamma-rays than the combined luminosity of all of the stars in our Milky Way galaxy. Prior to its strong outbursts in 2011, blazar 4C +71.07 was a weak source for Fermi's LAT. This renewed activity came after a long slumber, and that's important because it allows us to explicitly link the gamma-ray flares to the rising emission observed by radio telescopes. Theorists expect gamma-ray outbursts from blazars and other type of active galactic nuclei (AGN) occur only in close proximity to an AGN's central black hole, the central engine ultimately responsible for the activity and variability. A few rare observations suggested this is not the case.
Using a combination and correlation of gamma-ray flux variability monitoring data obtained with Fermi LAT and radio flux-structure data obtained with the VLBA on 4C +71.07 at different epochs, astrophysicists have discovered the clearest and most distant evidence that the theory still needs some work. Surprising the gamma-ray emission originated from a blob of plasma placed about 70 light-years away from the 4C +71.07 galaxy's central black hole.
(... read more).
Dec 10, 2012

Fermi Improves its Vision for Thunderstorm Gamma-Ray Flashes

Thanks to improved data analysis techniques and a new operating mode, the Gamma-ray Burst Monitor (GBM) aboard NASA's Fermi Gamma-ray Space Telescope is now 10 times better at catching the brief outbursts of high-energy light mysteriously produced above thunderstorms on our Earth. These atmospheric outbursts, known as terrestrial gamma-ray flashes (TGFs), last only a few thousandths of a second, but their gamma rays rank among the highest-energy light that naturally occurs on Earth. On April 2012 ASDC hosted a Workshop on "Lightning, Terrestrial Gamma-Ray Flashes, and Meteorology" in the frame of the AGILE Mission. The enhanced Fermi GBM discovery rate is helping scientists show most TGFs also generate a strong burst of radio waves, a finding that will change how scientists study this poorly understood phenomenon (... read more).
July 24, 2012

Fermi Epicycles: The Vela Pulsar's Path.

Exploring the cosmos at extreme energies, the Fermi Gamma-ray Space Telescope orbits planet Earth every 95 minutes. By design, it rocks to the north and then to the south on alternate orbits in order to survey the sky with its Large Area Telescope (LAT). The spacecraft also rolls so that solar panels are kept pointed at the Sun for power, and the axis of its orbit precesses like a top, making a complete rotation once every 54 days. As a result of these multiple cycles the paths of gamma-ray sources trace out complex patterns from the spacecraft's perspective, like this mesmerising plot of the path of the Vela Pulsar.
Centered on the LAT instrument's field of view, the plot spans 180 degrees and follows Vela's position from August 2008 through August 2010. The concentration near the center shows that Vela was in the sensitive region of the LAT field during much of that period. Born in the death explosion of a massive star within our Milky Way galaxy, the Vela Pulsar is a neutron star spinning 11 times a second, seen as the brightest persistent source in the gamma-ray sky. It was NASA's Astronomy Picture of the Day (APOD) for May 04, 2012.





The theory of epicycles, the idea that celestial bodies moved in small circles as they traced larger orbits with Earth as center, is arguably the most famous aspect of Ancient Greek astronomy (Ptolemy).
In the Ptolemaic system of astronomy, the epicycle (literally: on the circle in Greek) was a geometric model used to explain the variations in speed and direction of the apparent motion of the Moon, Sun, and planets. It was first proposed by Apollonius of Perga at the end of the 3rd century BC and formalized by Ptolemy of the Thebaid in his 2nd-century AD astronomical treatise the Almagest.
In 16th century Tycho Brahe, an eccentric Danish nobleman and astronomer made very accurate measurements of Mars' positions and compiled the voluminous astronomical data which Kepler would use to construct his theories. Brahe postulated that even in the Copernican system, epicycles were required and believed in a variation of the Ptolemaic system in which the planets went around the Sun, but the Sun went around the Earth. Galileo made telescope observations that supported the Copernican view, satellites rotating around Jupiter, and the Kepler's revised heliocentric system was demostrated to give far more accurate description of planetary motions than the Ptolemaic one.
The Copernican revolution was arguably completed by Isaac Newton whose "Philosophiae Naturalis Principia Mathematica" (1687) provided a consistent physical explanation which showed that Earth and the other planets are kept in their orbits around the Sun by the familiar force of gravity.

June 12, 2012

Happy 4th Birthday Fermi!

Today is the 4th anniversary of the Fermi Gamma-ray Space Telescope launch. In the past 4 years Fermi collected, through the main instrument the Large Area Telescope (LAT), over 1.37 billion of events (and 193 million of gamma-ray photon events ready for science analysis), distributed as public data by FSSC-GSFC and by the public Fermi data retrieval at ASDC.

https://tools.ssdc.asi.it/?searchtype=fermi

The LAT Collaboration has published 199 papers (Cat.I and Cat.II). Collectively these papers have been cited nearly 10,000 times. The LAT's fellow passenger on the Fermi satellite, the GBM has triggered on 1949 transients (and at 939 GRBs are creeping ever closer to the 1000 mark). The observatory has performed 77 autonomous repoints and the mission overall has produced over 800 refereed papers with new Fermi results or using/interpreting Fermi results and issued over 30 press/web releases.
The most recent press release reports first Fermi LAT analysis results about the highest-energy, MeV-GeV, gamma-ray photons detected from the Solar Flare of March 7 (the flare occurred during the days of the last Fermi LAT collaboration meeting held in Abano Terme, Padova, and during a Flare Advocate duty shift performed by a member of the ASDC Fermi Team).

Here below the Astronomy Picture of the Day, related to this Fermi Solar Flare:

http://apod.nasa.gov/apod/ap120315.html

and the recent NASA Press Release issued on June 11:

http://www.nasa.gov/mission_pages/GLAST/news/highest-energy.html

Here the Fermi LAT all-sky photon counts map of March 7, 2012 (E>100 MeV), showing that although the Vela pulsar is the brightest continuous LAT source, it was outmatched this day by the X5.4 solar flare, which brightened the gamma-ray sun by 1000 times.



A special cake has been made to celebrate the 4th Fermi's launch birthday. This is shown in the picture below (a large size cake containing a delicious combination of chocolate and vanilla).
January 27, 2012Fermi LAT detection of bright gamma-ray flux related to the strong solar flare of January 23 2012

The Fermi Large Area Telescope (LAT) detected on January 23, 2012, a very bright and high energy (E>100 MeV) gamma-ray activity from the sun produced by the strong M9-class solar flare erupting on the Sun's northeastern hemisphere at 03:59 UT. This event is resulting the strongest solar flare and radiation storm since 2005 bombarding our Earth. It has been produced by sunspot 1402 with a very fast coronal mass ejection (CME) partially Earth directed (see, for example this video, this video and this video).

A rush of radiation in the form of solar protons already has begun bombarding the Earth and is likely to continue through Thursday 26. The radiation storm is the largest of its kind since 2005 but still ranks only a three on the scale of one to five, enough to be considered ''strong'', with the potential to disrupt some communications and satellite systems and to bring auroras to high-latitude skies, but not ''severe''.

Following one of the longest and weakest periods of activity in many cycles, the Sun is brimming with activity again, and this flare is a preview of what may be to come in the solar maximum of 2012�13, having attracted the attention of the main newspapers and media. A solar eruption and flare is followed by a one-two-three punch. First comes electromagnetic radiation, followed by cosmic rays mostly in form of energetic protons (90%), helium nuclei (alpha particles) and electrons. Then, finally the coronal mass ejection (the plasma from the sun itself), hits the Earth. Usually that travels at about 2 or 3 million km/h, but this storm is particularly speedy and is shooting out at about 6.4 million km/h. It is the plasma that causes much of the noticeable problems on Earth, such as electrical grid outages.

During the first half of Jan. 23 (UT) the Large Area Telescope, one of the two instruments on the Fermi Gamma-ray Space Telescope, detected a long-lasting and bright gamma-ray emission positionally consistent with the Sun position on the sky at the time of the flare. First results indicates that gamma-ray emission above 100 MeV from the Sun during the brightest flux peak was a factor of about 50 greater than the gamma-ray flux of the solar disk for the quiet Sun ATel#3886. During this event the Sun was detected as the brightest gamma-ray point source of the E>100MeV sky, overwhelming the brightness of the Vela pulsar (see the figure below).



Fermi LAT reported other episodes of enhanced gamma-ray activity from the Sun on last year (ATel#3214, ATel#3417, ATel#3552, ATel#3635). These results followed Fermi LAT Data Quality Monitor duty service, LAT Solar science group analysis and LAT Flare Advocate and Gamma-ray Sky Watcher (FA-GSW) duty service (Ciprini et al. 2012, eConf C11/05/09, arXiv:1111.6803). The FA-GSW service provides for a day-by-day quicklook review of the high-energy gamma-ray sky seen by Fermi LAT, offering alerts for potentially new gamma-ray sources, interesting transients and relevant flares of celestial sources. A public weekly digest containing the main highlights is published in the Fermi Gamma-ray Sky Blog. The FA-GSW service is coordinated by the Fermi Team at ASDC and, in particular, the duty shifter during this solar flare event was S. Ciprini of ASDC (INAF).
November 29, 2011

The origin of Galactic cosmic rays is unveiled by recent results of AGILE and Fermi

The problem of the origin of Galactic cosmic rays has puzzled astronomers since their discovery nearly a century ago. Cosmic rays are energetic subatomic particles - about 89% protons, 10% helium nuclei, and 1% electrons - that impact the Earth's atmosphere from all directions.

The galaxy's best candidate sites for cosmic-ray acceleration are the rapidly expanding shells of ionized gas and magnetic field associated with supernova explosions. Providing an unambiguous proof of the cosmic-ray origin has been until now elusive, despite many decades of attempts and controversial claims.

ASI's AGILE and NASA's Fermi satellites are using gamma-rays to probe likely sites of cosmic-ray acceleration.

AGILE has recently discovered a pattern of gamma-ray emission from the supernova remnant W44 that, combined with the observed multifrequency properties of the source, can be unambiguously attributed to accelerated protons interacting with nearby dense gas.

The AGILE gamma-ray imager reaches its optimal sensitivity just at the energies in the 50 MeV-a few GeV range at which neutral pions (produced by proton-proton interactions) decay in gamma-rays producing an unambiguous signature.

The AGILE data resolves the problem of clearly identifying a source of energetic cosmic rays in our Galaxy exactly one hundred years after the discovery of cosmic rays by Victor Hess in 1912.

Cosmic rays may also come from clusters of massive, young stars called OB associations.

Observing the heart of the Cygnus constellation (the region of Cygnus X source) the Fermi Large Area Telescope (LAT) has recently found that cosmic rays are accelerated in the turbulent medium of a "cocoon" region where massive, hot, blue and windy stars are forming. The 1-100 GeV gamma-ray images reveal a 50-parsec-wide young super bubble of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters.

The well known Gamma Cygni supernova remnant also lies within this region. The Fermi team considers it possible that the supernova remnant engendered the cosmic rays trapped in the Cygnus X cocoon, but they also suggest an alternative scenario where the particles became accelerated through repeated interaction with shockwaves produced inside the cocoon by powerful stellar winds.

ASI supports data analysis for both AGILE and Fermi at the ASI Science Data Center in Frascati.

More information in:

AGILE article: A. Giuliani et al. ApJ 742, 2011
See also INAF news, ASI news, Italian Press Release, English Press Release

Fermi article: Science Vol. 334, 2011
See also INAF news, NASA news




Figure Credits: S. Ciprini combining AGILE Team, G. Castelletti, G. Dubner Images and NASA/DOE/Fermi LAT Images

November 23, 2011Identification of a further gamma-ray flaring blazar following fruitful Fermi-Swift synergy

The Large Area Telescope on the Fermi Gamma-ray Space Telescope, has recently observed, for the first time since launch, gamma-ray flaring activity from a source positionally associated with the flat spectrum radio quasar OG 050 (also known as TXS 0529+075 and 2FGL J0532.7+0733, with redshift z=1.254 and provided of bright X-ray and radio jet), see ATel#3750.
Following this GeV flare, rapid Swift ToO observations were requested thanks to the Fermi Flare Advocate duty and were performed when the source was still in an active state. Swift XRT and UVOT quicklook data reduction performed through the ASDC online analysis tools, revealed on 2011 Nov. 11 a simultaneous high brightness state at GeV, X-ray and UV energy bands, and a simultaneous lower, post-flare, state four days later, confirming the firm identification of the associated flaring gamma-ray source with the blazar OG 050, see ATel#3773.
Again the Swift satellite, thanks to its broad band coverage and scheduling flexibility, has created a perfect synergy with Fermi in high-energy astrophysics.
November 4, 2011Fermi Finds Youngest Millisecond Pulsar, reaching 100 gamma-ray pulsars

An international team of scientists using NASA's Fermi Gamma-ray Space Telescope has discovered a surprisingly powerful millisecond pulsar that challenges existing theories about how these objects form. At the same time, another team has located nine new gamma-ray pulsars in Fermi data, using improved analytical techniques.

More Information available on:
http://www.nasa.gov/mission_pages/GLAST/news/young-pulsar.html

In italian (by INAF):
http://www.media.inaf.it/2011/11/03/una-giovane-pulsar-per-fermi/
August 25, 2011Results on extensive Planck, Swift, and Fermi simultaneous observations of blazars available on arXiv/astro-ph

A paper reporting the results of a large-scale collaboration involving the Planck, Swift, and Fermi teams, which led to simultaneous multi-frequency observations of a large number of blazars, has been submitted to A&A and is available on arXiv/astro-ph.
August 23, 20112-year Fermi-LAT Catalogs Released

The Fermi-LAT collaboration presented the second catalog of gamma-ray sources (2FGL) and the second catalog of LAT Active Galactic Nuclei (2LAC), For a full explanation about the catalogs and their content see the "LAT 2-year Catalog Paper" and the "LAT 2-year AGN Catalog Paper" on arxiv.

The 2FGL and 2LAC Catalogs are now available as ASDC interactive tables at https://www.ssdc.asi.it/fermi2fgl/ and https://www.ssdc.asi.it/fermi2lac/ .
2FGL lists 1.873 gamma-ray sources, 589 of which remain unidentified and could represent entirely new cosmic objects.
April 19, 2011

New Crab Nebula enhanced activity and unprecedented giant flare in gamma-rays

A renewed increase of the gamma-ray activity above 100 MeV from the Crab Nebula has been recently reported by Fermi in ATel #3276 (R. Buheler at al.) in the period April 9-11, 2011, and confirmed by the AGILE monitoring in ATel #3282 (M. Tavani et al.).

We recall that a gamma-ray flux increase from the direction of the Crab Nebula was reported for the first time by AGILE, and then confirmed by Fermi in September 2010 (ATel #2855 and ATel #2861).

Fermi satellite began a pointed mode observation of the Crab Nebula in response to the recent observed increase in gamma-ray activity.

A ToO Swift/XRT observation was also promptly performed but no significant X-ray flux variation was detected, as reported in ATel #3279 (G. Cusumano et al.).

Chandra was observing the Crab on April 12 and 13, 2011 as part of their monitoring program, which began following the previous surprising gamma-ray flare in September 2010. Chandra observations are reported in ATel #3283 (A. Tennant et al.).

A very strong gamma-ray flare was then detected by AGILE on April 16, 2011, see ATel #3286 (E. Striani et al.). The flux above 100 MeV reached the unprecedented value of F = (20.0 ± 3.7) 10^{-6} ph/cm2/sec. The detected gamma-ray flux from the Crab was then twice as bright as the Vela Pulsar.



Credits: Image background X-ray: NASA/CXC/ASU/J.Hester et al.; Optical: NASA/HST/ASU/J.Hester et al., AGILE (ASI) and Fermi (NASA) satellites.
April 15, 2011Renewed increase of gamma-ray activity from the Crab Nebula

A renewed increase of the gamma-ray activity above 100 MeV from the Crab Nebula has been recently reported by Fermi in ATel #3276 (R. Buheler at al.) in the period April 9-11, 2011, and confirmed by the AGILE monitoring in ATel #3282 (M. Tavani et al.).

A ToO Swift/XRT observation was promptly performed but no significant X-ray flux variation was detected, as reported in ATel #3279 (G. Cusumano et al.).

Chandra was observing the Crab on April 12 and 13, 2011 as part of their monitoring program, which began following the previous surprising gamma-ray flare in September 2010.
We recall that a gamma-ray flux increase from the direction of the Crab Nebula was reported for the first time by AGILE, and then confirmed by Fermi in September 2010 (ATel #2855 and ATel #2861).

The new Chandra observations are reported in ATel #3283 (A. Tennant et al.).
March 9, 2011III Fermi Symposium :ABSTRACT SUBMISSION OPEN!

Dear Colleague,

We are pleased to announce that abstract submission and registration for the 3rd Fermi symposium is now open. Please visit the web pages at http://fermi.gsfc.nasa.gov/science/symposium/2011/ for information about the meeting.

Registration:
The symposium registration fee is 350 Euro until April 8. There is a reduced fee for current students of 250 Euro. After April 8, the fee will increase to 450 Euro (and 350 Euro for students). Registration includes lunch each day, a tour of the Sistine Chapel and a social dinner.

Abstract submission:
We invite participants to submit abstracts for proposed scientific contributions to the symposium. The default mode of contributions will be posters. The scientific organising committee will select a subset of the abstracts for oral presentations in either plenary or parallel sessions. In addition to Fermi science, poster and parallel oral contributions on relevant analysis techniques and the status of related facilities (current and future) are welcome. For poster contributions, we are continuing the procedure from the last Fermi symposium: all posters should have a two-line abstract summary displayed at the top. The condensed summary, along with an optional more detailed abstract, will be included on the program website. The deadline for abstract submission is March 20 2011. ABSTRACT SUBMISSION IS NOW OPEN.

Hotel reservations:
The symposium webpage has links to lists of hotels in Rome, their distance from the symposium site and details on how to make reservations. Hotels in Rome are typically busy in May, so we encourage participants to make reservations early to ensure a place at the hotel of their choice.

Program updates:
We have updated the program to provide an updated block program and a list of the invited talks and speakers.
January 21, 2011

Fermi Team wins Top High-Energy Prize 'Bruno Rossi'

The 2011 Rossi Prize has been awarded to Bill Atwood, Peter Michelson and the Fermi-LAT team "for enabling, through the development of the Large Area Telescope, new insights into neutron stars, supernova remnants, cosmic rays, binary systems, active galactic nuclei, and gamma-ray bursts".

The American Astronomical Society (AAS) High Energy Astrophysics Division (HEAD) awards the Rossi Prize in recognition of significant contributions as well as recent and original work in high-energy astrophysics. The prize is in honor of Professor Bruno Rossi, an authority on cosmic ray physics and a pioneer in the field of X-ray astronomy. The winners of the Rossi Prize will give a joint lecture at the 219th AAS meeting in Austin, Texas in January 2012.

The Fermi Gamma-Ray Space Telescope, formerly GLAST, is an international and multi-agency space observatory that studies the cosmos in gamma-rays, the most energetic form of light. The LAT is one of two instruments onboard Fermi and is the most sensitive and highest-resolution gamma-ray detector ever launched.

The ASDC is actively involved in the Fermi collaboration playing an important role in the development of the LAT scientific and data analysis software, especially for the automatic data processing, developing the software for the publication of LAT catalogues and the distribution of high level data products.
ASDC staff is also contributing to many scientific activities within the Fermi LAT collaboration particularly in the fields of AGN, GRB and in multi-frequency data analysis. The Fermi team at ASDC is composed of:
P. Giommi: full member, former AGN Science group coordinator in years 2006-2008,
E. Cavazzuti: full member, one of the current AGN Science group coordinators and leader of Fermi team in ASDC,
S. Cutini: post doc member with main research activity on GRB, AGN and catalog production,
D. Gasparrini: post doc member, one of the Flare Advocate team coordinators with main research activity on AGN and catalog production,
R. Primavera: technical member with activity on software programming (in particular the 'Quick Look' named Automatic Science Processing),
C. Pittori and M. Perri: affiliated members with activity in multi-frequency data analysis.

This is the third time that members of the ASDC have been awarded a Bruno Rossi Prize after BeppoSAX in 1998 and Swift in 2007.

For more information about Fermi, visit: http://fermi.asdc.asi.it, http://www.nasa.gov/fermi

Information on previous winners of the Rossi Prize can be found at http://www.aas.org/head/rossi/rossi.recip.html
January 12, 2011Fermi Catches Thunderstorms Hurling Antimatter into Space

Scientists using Fermi Gamma-ray Space Telescope have detected beams of antimatter produced above thunderstorms on Earth. They think the antimatter particles were formed in a terrestrial gamma-ray flash (TGF), a brief burst produced inside thunderstorms and shown to be associated with lightning

More Information available on:
http://www.nasa.gov/mission_pages/GLAST/news/fermi-thunderstorms.html
November 10, 2010Fermi Finds Giant Bubble Structure in our Galaxy

Fermi Gamma-ray Space Telescope has unveiled a previously unseen structure centered in the Milky Way. The feature spans 50,000 light-years and may be the remnant of an eruption from a supersized black hole at the center of our galaxy.

More information are available on:
http://www.nasa.gov/mission_pages/GLAST/news/new-structure.html
June 21, 2010AGILE and Fermi detection of intense gamma-ray flare from the blazar 4C+21.35 (PKS 1222+21)

New AGILE ATel issued: ATel #2686 (E. Striani et al.)
New Fermi ATel issued: ATel #2687 (G. Iafrate et al.)

On June 19, 2010, AGILE and Fermi reported the detection of intense gamma-ray emission above 100 MeV from the Flat Spectrum Radio Quasar 4C+21.35, also known as PKS 1222+21.
Flaring activity from this source has been also detected in the past few days by the MAGIC (ATel #2684) at energies above 100 GeV.
March 25, 2010

FERMI 1-year Catalogs now on line!

The Fermi Large Area Telescope (LAT) collaboration released a milestone catalog of the high-
energy gamma-ray sources detected by the LAT and a study of the active galaxies that make
up the majority of gamma-ray sources outside the Milky Way.

These catalogs are available on-line along with multifrequency tools and Fermi-LAT data products. The links
are
https://www.ssdc.asi.it/fermi1lac/ and https://www.ssdc.asi.it/fermi1fgl/

This catalog is denoted 1FGL for first Fermi Gamma-ray LAT.The Fermi observatory completed the first year of
its science mission in August 2009, and the 1FGL is based on analysis of most of the first-year data, for the
energy range 100 MeV - 100 GeV. The 1FGL catalog is the deepest and most complete catalog of high-energy
gamma-ray sources obtained to date. It has 1451 sources, several times more gamma-ray sources than all
previous catalogs at these energies. The position determinations are typically accurate to
within 10 arcmin and the 1FGL catalog includes measurements of the fluxes in 5 bands and
light curves in 11 time intervals for each source (http://arxiv.org/abs/1002.2280v1);.

The 1FGL catalog is an important resource for many studies, including discovery and
characterization of new populations of GeV gamma-ray emitting sources. The field is young, and the LAT has
deepened the sensitivity of the observations enough, that more theoretically plausible populations of gamma-
ray sources were known than have been firmly identified in the past. With the first-year results and the 1FGL
catalog the LAT team is reporting evidence for several new populations, including millisecond pulsars,
'misaligned jet source' active galaxies, and starburst galaxies as populations. Other potential populations, such
as X-ray binaries (including microquasars) and globular clusters, are looking promising.

For the established and new populations, the 1FGL catalog also includes a quantitative
assessment of potential counterparts (`associations') at other wavelengths. Positional
association is not equivalent to identification of a source, but the method defines potential
gamma-ray members of the source classes, and as importantly reveals which sources have
no obvious counterparts among the established source classes. The LAT collaboration found
631 such unassociated sources, using a conservative definition of positional association. The
relatively large fraction of unassociated sources points to the discovery potential still to be
realized in the LAT data.

More than 100 of the unassociated sources are located in or near the plane of the Milky Way,
where the diffuse gamma-ray glow of the Milky Way makes detection and characterization of
gamma-ray sources especially difficult. The challenge for many of these 1FGL sources may
be as much about understanding the diffuse emission from cosmic-ray collisions with gas
and photons as about identifying the sources.

By far the largest population of associated gamma-ray sources in the 1FGL catalog are active
galaxies, whose gamma-ray emission is powered by jets of plasma accelerated in their
nuclear regions, where matter is being accreted onto massive black holes. The First LAT
Active galaxies Catalog (1LAC) presents a comprehensive study of the populations of these
blazars in the 1FGL data set (http://arxiv.org/abs/1002.0150);. For this statistical study, a lower confidence
level for associated sources was acceptable, and 1LAC includes more than 800 1FGL sources. The 1LAC
catalog integrates observations from radio wavelengths to TeV energies to characterize the active galaxies,
and 3 populations are recognized and characterized in terms of their gamma-ray spectra, variability, and
luminosities, together with properties measured at other wavelengths. The 1LAC represents by far the largest
sample of gamma-ray active galaxies ever available and is a valuable reference and resource for study of
active galaxies and populations of active galaxies.
February 17, 2010Helical magnetic fields in the Jet of the quasar 3C 279?

(17 Feb. 2010) A large multi-wavelength observational campaign, involving 250 scientists and 20 ground and space telescopes, was organized to study the blazar 3C 279 during the first year in orbit of the Fermi gamma-ray space telescope.
The unexpected important result, just published in Nature, came from the combination of optical polarimetric observations with gamma-ray data.
The insights into the structure of quasar jets from gamma-ray and optical polarimetric observations show a non-axisymmetric jet structure implying a curved trajectory for the emitting material within the jet, with the dissipation region located at a considerable distance from the black hole.
This may suggest that the flaring activity is indeed related to the change of geometry and/or viewing angle rather than to the acceleration and cooling event in the jet.
March 25, 2010Fermi Closes on Source of Cosmic Rays

(16 Feb. 2010)New images from Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. Cosmic rays consist mainly of protons that move through space at nearly the speed of light. In their journey across the galaxy, the particles are deflected by magnetic fields. This scrambles their paths and masks their origins. Fermi's Large Area Telescope (LAT) mapped billion-electron-volt (GeV) gamma-rays from three middle-aged supernova remnants -- known as W51C, W44 and IC 443 -- that were never before resolved at these energies. (The energy of visible light is between 2 and 3 electron volts.) Each remnant is the expanding debris of a massive star that blew up between 4,000 and 30,000 years ago. In addition, Fermi's LAT also spied GeV gamma rays from Cassiopeia A (Cas A), a supernova remnant only 330 years old. Ground-based observatories, which detect gamma rays thousands of times more energetic than the LAT was designed to see, have previously detected Cas A.

August 31, 2009August 25, Fermi-LAT data now public!


(31 Aug. 2009)We are pleased to announce that the LAT level-1 data products are now publicly available!Currently photon event lists and associated auxiliary files needed for the analysis are available for download from the FSSC web site (http://fermi.gsfc.nasa.gov/ssc);.
Shortly Fermi-LAT data will be retrievable from the ASDC web site where on-line quick look analysis tools will also be provided.
ASDC experienced personnel is already available for support in detailed data analysis.
May 4, 2009

NASA's Fermi Explores High-energy "Space Invaders"

Since its launch last June, NASA's Fermi Gamma-ray Space Telescope has discovered a new class of pulsars, probed gamma-ray bursts and watched flaring jets in galaxies billions of light-years away. Today at the American Physical Society meeting in Denver, Colo., Fermi scientists revealed new details about high-energy particles implicated in a nearby cosmic mystery.

For more details see:
http://www.nasa.gov/mission_pages/GLAST/news/space_invaders.html
August 31, 2009August 25, Fermi-LAT data now public!

We are pleased to announce that the LAT level-1 data products are now publicly available!
Currently photon event lists and associated auxiliary files needed for the analysis are available for download from the FSSC web site (http://fermi.gsfc.nasa.gov/ssc);.

Shortly Fermi-LAT data will be retrievable from the ASDC web site where on-line quick look analysis tools will also be provided.

ASDC experienced personnel is already available for support in detailed data analysis.
February 10, 2009Fermi-LAT Bright Source List released

The Fermi-LAT Bright Source List has been released on February 9th, 2009.
The list is available at ASDC and at the Fermi Support Center.
For a full explanation about the source list and its construction see here.
August 28, 2008NASA Renames GLAST as Fermi Gamma-ray Space Telescope

The Gamma-ray Large Area Space Telescope, or GLAST, has begun its mission of exploring the universe in high-energy gamma rays.
The spacecraft and its revolutionary instruments passed their orbital checkout with flying colors.

NASA announced August 26 that GLAST has been renamed the Fermi Gamma-ray Space Telescope. The new name honors Italian-American Nobel Prize Enrico Fermi (1901-1954), a pioneer in high-energy physics.

ASI Press release: http://www.asi.it/SiteEN/Default.aspx
NASA Press release: http://www.nasa.gov/mission_pages/GLAST/news/glast_findings_media.html