GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"20957 results found.
- GRB 151111A: GROND confirmation of the afterglow and photometric redshift estimate
- GRB 151112A: Swift/UVOT Upper Limits
- GRB 151112A: GROND Detection of the Optical/NIR Afterglow Candidate
- GRB 151112A: initial UVOT observations
- GRB 151112A: Swift-XRT observations
- GRB 151111A: Swift/UVOT upper limits
- GRB 151111A: GROND marginal detection of a afterglow candidate
- LIGO/Virgo G194575: VLA follow-up
- GRB 151111A: LCOGT-FTS afterglow observations
- GRB 151107B: MASTER-NET OT detection inside the FERMI error box
- GRB 151027A: continued Mondy optical observations
- LIGO/Virgo G194575: Liverpool Telescope observations of iPTF-15dld and iPTF-15dni
- LIGO/Virgo G194575: La Silla QUEST, Pan-STARRS and PESSTO observations of iPTF15dld
- LIGO/Virgo G194575: Swift observations if iPTF15dld
- GRB 151027A: Hankasalmi optical observations
- LIGO/Virgo G194575: INAF-TNG/Asiago Telescope follow-up of iPTF15dld
- GRB 151107A: MASTER-NET optical observations
- LIGO/Virgo G194575: INAF-Asiago Telescope further analysis of iPTF candidates
- Swift-BAT triggers are disabled
- LIGO/Virgo G194575: INAF-Asiago Telescope follow-up of iPTF candidates
- LIGO/Virgo G194575: VLA follow-up
- GRB 151027A: Mondy optical observations
- GRB 150910A: CrAO optical observations
- GRB 151027A: Correction to GCN 18519
- GRB 151031A: GROND observation
- LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
- GRB 151031A: Swift/UVOT Detection
- GRB 151031A: VLT/X-shooter optical counterpart and redshift
- GRB 151027A: optical follow-up observations
- GRB 151027A: Continued P60 Monitoring
- GRB 151029A: Swift/UVOT Detection
- GRB 151029A: LCOGT-FTS afterglow observations
- GRB 151027B: Swift UVOT detection
- LIGO/Virgo G194575: VLA follow-up
- GRB 151027A: MAXI/GSC detection
- GRB 151029A VLT/X-shooter redshift
- GRB 151029A: GROND afterglow observations
- GRB 151027A: SAO RAS optical observations
- GRB 151027B: LCOGT FTN afterglow observations
- GRB 151027A: NOT optical and NIR observations
- GRB 151027A: T100 observations
- GRB 151027B: Swift/UVOT Upper Limits
- GRB 151027A : Xinglong TNT optical observation
- GRB 151027A: continued GMG observation
- GRB 151027B: RATIR Observations
- GRB 151027B: MASTER-NET early OT detection
- GRB 151027A: LCOGT-McDonald afterglow observations
- GRB 151027A: VLA detection
- GRB 151027B: GROND Optical/NIR Afterglow Detection
- GRB 151027B: VLT/X-shooter redshift
- GRB 151027A: THO optical observations
- GRB 151027A: UVOT Observations
- GRB 151027B: NOT optical afterglow candidate
- LIGO/Virgo G194575: iPTF Optical Transient Candidates
- GRB 151027A: Early RAPTOR Observations
- LIGO/Virgo G194575: MASTER Optical Inspection
- GRB 151027A: GMG observation
- LIGO/Virgo G194575: Swift observations of LSQ15bjb
- LIGO/Virgo G194575: GROND multi-color observations
- GRB 151027A: Weihai optical observations
- LIGO/Virgo G194575: further Pan-STARRS observations of the RA=1hr localisation region
- GRB 151027A: P60 afterglow confirmation and rebrightening
- GRB 151027A: KAIT optical afterglow confirmation
- LIGO/Virgo G194575: ASKAP followup
- LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
- LIGO/Virgo G194575 : La Silla - QUEST followup
- GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
- LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
- LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
- LIGO/Virgo G194575: Pi of the Sky observations
- LIGO/Virgo G194575: MAXI/GSC observations
- LIGO/Virgo G194575: Swift observations
- GRB 151022A: OSN optical upper limit
- GRB 151023A: RATIR Observations
- GRB 151023A: Swift/UVOT Upper Limits
- GRB 151023A
- LIGO/Virgo G194575: CQUEAN/LOAO observations
- LIGO/Virgo G194575: LOFAR follow-up
- GRB 151022A: Swift/UVOT Upper Limits
- LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
- LIGO Virgo G194575: MWA Observations
- LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
- LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
- LIGO/Virgo G194575: Fermi GBM Observations
- LIGO/Virgo G194575: Mini-MegaTORTORA observations
- LIGO/Virgo G194575: transients from Pan-STARRS in the RA=1hr localisation region
- LIGO Virgo G194575: TZAC TAROT observations
- GRB 151022A: MITSuME Okayama Ks-band upper-limit
- GRB 151022A: MASTER-Ural observations
- GRB 151021A: MITSuME Okayama Ks-band upper-limit
- GRB 151021A: Swift/UVOT Detection
- LIGO/Virgo G184098: LOFAR follow-up
- GRB 151004A: Swift-XRT follow-up observations
- Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
- LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
- LIGO/VIRGO G184098 : PESSTO classifications of PanSTARRS transients in the northern region
- GRB 151006A: OSN optical upper limit
- GRB 151006A: MITSuME Okayama Ks-band upper-limit
- GRB 151006A: Swift/UVOT Upper Limits
- LIGO/Virgo G184098: Further VST-ESO PARANAL observations