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').
Advanced Search
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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"16293 results found.
- LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
- LIGO/Virgo S190426c: GROWTH India follow-up of GRAWITA transient
- LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
- LIGO/Virgo S190425z: 1.3-m optical imaging of UVOT transient field
- LIGO/Virgo S190426c: YAHPT Optical Observation
- LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
- LIGO/Virgo S190425z: MASTER detection of the faint flare in SDSS Seyfert galaxy z = 0.09
- LIGO/Virgo S190426c: Continued LOAO Observation
- GRB 190427A: Swift/UVOT Upper Limits
- LIGO/Virgo S190426c: Additional Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190426c: Continued infrared wide-field search with Palomar Gattini-IR
- LIGO/Virgo S190425z: MASTER explanation of the nature of an optical flash detected by a Swift as a short flare on a fast-moving WISE brown
- LIGO/Virgo S190426c: ASAS-SN observations
- LIGO/Virgo S190426c: LOAO Observation
- LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
- LIGO/Virgo S190425z: NOT photometry of ZTF19aasckkq
- LIGO/Virgo S190426c: DG19ytre and DG19kplb 1.5m OSN imaging and 10.4m GTC spectroscopy
- LIGO/Virgo S190425z: Liverpool Telescope imaging of ZTF19aasckkq
- LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient in ASAS-SN observations hours before and after discovery
- LIGO/Virgo S190425z: Additional Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
- LIGO/Virgo S190425z: ASAS-SN observations
- LIGO/Virgo S190425z: No Optical Detection of the Swift/UVOT Transient with Las Cumbres Observatory
- LIGO/Virgo S190425z: Swift/UVOT and XRT pre-images at the position of the potential Swift/UVOT counterpart
- LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
- LIGO/Virgo S190426c: J-GEM optical/NIR follow-up observations
- LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
- LIGO/Virgo S190426c: GOTO optical coverage - no notable counterparts
- GRB 190427A: Lick/Nickel telescope optical observations
- GRB 190427A: MITSuME Akeno optical upper limits
- GRB 190427A: COATLI Optical Observations
- LIGO/Virgo S190426c: CNEOST Optical Observations
- LIGO/Virgo S190425z: CNEOST Optical Observations
- LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
- GRB 190427A: RATIR Optical and NIR Observations
- LIGO/Virgo S190426c: Nanshan/NEXT Observation of Galaxies
- LIGO/Virgo S190426c: Hobby-Eberly Telescope VIRUS observations of target galaxies.
- GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
- GRB 190427A: NOT optical observations
- LIGO/Virgo S190426c: Public DECam Observations
- LIGO/Virgo S190425z: GRAWITA LBT spectroscopic observations
- LIGO/Virgo S190426c: SAO optical observation
- LIGO/Virgo S190425z: YAHPT Optical Observation
- LIGO/Virgo S190425z: J-GEM spectroscopic observations of AT2019ebq/PS19qp with Subaru/FOCAS
- LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
- LIGO/Virgo S190425z: TAROT-GRANDMA observation report
- LIGO/Virgo S190425z: GOTO observations
- LIGO/Virgo GW190425z: GTC spectroscopic classification of AT2019ebq/PS19qp
- LIGO/Virgo S190425z: ZTF19aarzaod 1.5m OSN imaging and 10.4m GTC spectroscopy
- LIGO/Virgo S190425z: ZTF19aarzaod WHT spectroscopy
- LIGO/Virgo S190425z: GRAWITA TNG observations of ZTF19aarzaod
- LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
- LIGO/Virgo S190425z: KPED Follow-Up Observations
- LIGO/Virgo S190425z: ZTF19aarzaod Imaging from Las Cumbres Observatory
- LIGO/Virgo S190425z: Lulin Follow-Up Observations
- LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
- LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
- LIGO/Virgo S190425z: LOAO Observation
- LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
- GRB 190422A: Swift/UVOT Upper Limits
- Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
- GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
- LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
- LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
- LIGO/Virgo S190412m: MASTER early alert observation
- GRB 190409A: ground analysis reveals a likely spurious event
- LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
- LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
- GRB 190404C: MITSuME Akeno and Okayama optical upper limits
- LIGO/Virgo S190408an: TMTS Optical Observation
- LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
- LIGO/Virgo S190408an: HMT optical observations
- LIGO/Virgo S190408an: MASTER 3 OT's more detection
- LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
- LIGO/Virgo S190408an: MASTER OT detection
- LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
- LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
- Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
- Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
- GRB 190404C: Swift-XRT observations
- GRB190404C: GROWTH-India discovery of optical counterpart
- GRB 190330A: MITSuME Akeno and Okayama optical upper limits
- GRB 190331B: BOOTES-3/YA optical observations
- IceCube-190331A: MASTER optical follow-up observations
- GRB 190326A: 2.2m CAHA telescope optical limit
- GRB 190326A: MITSuME Okayama optical upper limits
- GRB190324A: MASTER OT observations
- GRB 190324A: VLT/X-shooter redshift
- GRB 190320A: Swift/UVOT Upper Limits
- GRB190320A: MASTER GRB counterpart decay
- GRB190311A: MITSuME Akeno optical observation
- Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
- GRB 190311A: OSN optical afterglow detection
- GRB 190311A: Mondy optical observations
- GRB 190311A: Liverpool Telescope observations
- GRB 190311A: NOT optical counterpart
- GRB190305A: MASTER Global Robotic Net optical observation
- GRB 190311A: Mondy optical observations
- GRB 190311A: GMG observation
- GRB 190311A: TSHAO optical observations