GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"21103 results found.
- Fermi trigger No 590335819: Global MASTER-Net observations report
- Alert from the HAWC Burst Monitor HAWC-190917A
- LIGO/Virgo S190915ak: no counterpart candidates in the Swift/BAT observations
- LIGO/Virgo S190915ak: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
- GRB190915A: MASTER optical observation of BALROG Fermi GRB localization
- LIGO/Virgo S190915ak: Upper Limits from AGILE-GRID observations
- LIGO/Virgo S190915ak: No counterpart candidate in AGILE-MCAL observations
- LIGO/Virgo S190915ak: Global MASTER-Net observations report
- LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
- Fermi trigger No 590038994: Global MASTER-Net observations report
- LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
- Baksan Neutrino Observatory Alert 190913.27: Global MASTER-Net observations report
- LIGO/Virgo S190910d: No Counterparts in DDOTI/OAN Optical Observations
- LIGO/Virgo S190910h: Upper limits from CALET observations.
- LIGO/Virgo S190910d: No transient candidates in CALET observations.
- LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
- LIGO/Virgo S190910h: Four additional candidates from the Zwicky Transient Facility
- LIGO/Virgo S190910h: Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190910d: Liverpool Telescope spectroscopy of ZTF19abyfazm
- LIGO/Virgo S190910h: no counterpart candidates in the Swift/BAT observations
- LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
- LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190910h: No counterpart candidates in AGILE-MCAL observations
- LIGO/Virgo S190910h Global MASTER-Net observations report
- LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190910d: no counterpart candidates in AGILE-GRID observations
- LIGO/Virgo S190910d: no counterpart candidates in the Swift/BAT Observations
- LIGO/Virgo S190910d: No counterpart candidates in AGILE-MCAL observations
- LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
- LIGO/Virgo S190910d Global MASTER-Net observations report
- LIGO/Virgo S190814bv: ATCA monitoring of ASKAP J005547-270433/AT2019osy
- LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
- LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
- Fermi trigger No 589561732 Global MASTER-Net observations report
- ZTF19abvizsw: 15GHz observations with AMI
- GRB 190829A observations in CrAO, photometry of the SN
- Fermi trigger No 589487114 Global MASTER-Net observations report
- GRB 190823A: Swift-XRT afterglow detection
- GRB 190829A: GTC confirmation of an associated Type Ic-BL Supernova
- GRB 190829A: ATCA cm-band detection
- LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
- Fermi trigger No 589419513 Global MASTER-Net observations report
- GRB 180620A: SEDM Observations
- LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
- LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
- LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
- LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
- LIGO/Virgo S190901ap: Dabancheng-0.5m optical observations of AT2019pjv
- Swift XRT Detection of X-ray Emission from ZTF19abvizsw
- GRB 190829A: Liverpool Telescope observations of a slow supernova rise
- LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
- ZTF19abvizsw: COATLI Optical Observations
- LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
- LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
- LIGO/Virgo S190901ap: MASTER OT J171434.95+280725.6/AT2019pjv detection
- LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
- LIGO/Virgo S190901ap: Upper limits from CALET observations.
- LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
- Fermi trigger No 589263065 Global MASTER-Net observations report
- Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
- GRB 190829A: LCO Optical Afterglow Detection
- Fermi trigger No 589223981 Global MASTER-Net observations report
- GRB 190829A: MeerKAT radio observation
- LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
- LIGO/Virgo S190901ap: GROWTH-India follow-up of ZTF19abvionh
- Chandra observations of GW170817 ~740-743 days since merger
- LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
- LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
- LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
- GRB 190829A: Detection of radio afterglow with the uGMRT
- LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
- LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh [correction on the peak]
- GRB 190829A: Flattening of optical light curve from continued Liverpool Telescope photometry
- LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh
- LIGO/Virgo S190814bv: ATCA observation of ASKAP J005547-270433/AT2019osy
- LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of target galaxy; no obvious optical counterpart.
- LIGO/Virgo S190901ap: no counterpart candidates in the Swift/BAT Observations
- LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190901ap: No counterpart candidates in AGILE-MCAL observations
- LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
- LIGO/Virgo S190901ap Global MASTER-Net observations report
- LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
- Fermi trigger No 589065714 Global MASTER-Net observations report
- Fermi trigger No 589060361 Global MASTER-Net observations report
- LIGO/Virgo S190814bv : No significant candidates in TAROT-GRANDMA observations
- GRB 190829A: Continued fading inferred from Liverpool Telescope photometry
- LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidate AT2019ntp
- GRB 190829A: Keck LRIS spectroscopy of the optical afterglow
- LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
- LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
- GRB 190829A: Liverpool Telescope observations
- Fermi trigger No 588962322 Global MASTER-Net observations report