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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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"23416 results found.
- GRB 080129: Swift-XRT refined analysis
- GRB 080129: KAIT optical limits
- GRB 080129: TAROT La Silla observatory optical observations
- GRB 080129: GROND detection in all bands, and fading
- GRB 080129: GROND detection of the optical/NIR afterglow, and fading
- GRB 080129: Enhanced Swift-XRT position
- GRB 080129: Gemini-South Imaging Observations
- GRB 080129 (?): UVOT Upper Limits
- GRB 080129 (?): Swift detection of a possible burst
- GRB 080121: Upper limit on X-ray afterglow
- GRB 080121: Swift/UVOT upper limits
- SNe 2008D and 2007uy: Chandra Detections
- GRB 080121: Enhanced Swift-XRT position
- IPN triangulation of GRB080122
- GRB 080121: Nearby SDSS galaxies
- GRB 080121: Swift-BAT detection of a very weak, short burst
- GRB 080123: Swift/UVOT refined analysis
- GRB 080123: Enhanced Swift-XRT position
- GRB 080123: Swift detection of a short burst
- GRB 080120: GROND confirmation of the optical afterglow
- VLA radio upper limit on GRB 080120
- UVOT detection of GRB080120
- GRB080120: Swift XRT position
- GRB 080120: a long GRB detected by INTEGRAL
- Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
- NGC 2770B has the same redshift as NGC 2770
- Swift UVOT Monitoring of the SN 2008D Brightening (Transient in NGC 2770)
- XRF 080109 / SN 2008D: UKIRT JHK imaging
- optical observations, XRT in NGC 2770
- XRF 080109/SN 2008D: PROMPT Optical Imaging
- Gemini-South observations of XRF 080109 / SN 2008D
- Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
- Discovery of Radio Emission from Transient in NGC 2770
- XRF 080109 in NGC2770: NIR observations at TNG
- XRB 080109/SN 2008D: Early decline in brightness and change in colors
- XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
- XRF 080109 in NGC2770: Detectable Superluminal Motion
- Spectroscopic classification of SN 2008D (Transient in NGC 2770)
- Refined Swift-XRT analysis of the transient in NGC 2770
- Refined Swift UVOT Analysis of SN 2008D (Transient in NGC 2770)
- Early OT detection of XRF in NGC 2770 in Asiago frames
- Possible XRF in NGC 2770 - NOT observations of the optical counterpart
- Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
- GRB 071227: optical afterglow
- Further Swift-BAT analysis of GRB 071227
- Konus-Wind observation of GRB 071227
- GRB 071227: Swift-XRT refined analysis
- GRB 071227: VLT probable redshift of the candidate host galaxy
- GRB 071227: Magellan observations
- GRB071227: Swift/UVOT refined analysis
- GRB 071227: REM NIR and Optical observations
- GRB 071227: Swift detection of a burst
- GRB 070429B: Possible UVOT Detection of an Optical Afterglow
- GRB 071208?: Swift detection of a possible burst
- GRB 071125: Suzaku WAM observation of the prompt emission
- GRB 070429B: Probable host galaxy and redshift
- GRB 071129, Swift-BAT refined analysis
- GRB 071129: Swift detection of a burst
- Konus-Wind and Konus-A observations of GRB 071125
- IPN triangulation of very bright GRB 071125
- GRB 071126: Enhanced Swift-XRT position
- GRB071122: Swift/UVOT Observations
- GRB071104: NIR Afterglow Candidate at TNG
- GRB 071122 Swift-XRT refined analysis
- GRB 071122: P60 Optical Afterglow Candidate
- GRB 071122: ROTSE-III Optical Limits
- GRB 071122: Swift detection of a burst
- GRB 071118: P60 Observations
- GRB071118 MITSuME OAO optical observation
- GRB 071118: Observations from OSN
- GRB 071117: VLT observations and probable redshift
- Swift/UVOT observations of GRB071118
- Swift XRT follow-up observations of GRB071008
- Swift/UVOT upper limits for GRB 071117
- GRB071118: Swift XRT refined analysis
- GRB 071117: Gemini Optical Afterglow Discovery
- GRB 071118, Swift-BAT refined analysis
- GRB 071117: TAROT La Silla observatory optical observations
- GRB 071112B: Gemini Image Differencing
- GRB 071118: Swift detection of a burst
- GRB 071117: Gemini Observations
- VLT FORS2 observations of short hard GRB071112B
- GRB 071117: Initial Swift/UVOT observations
- GRB 071117: Swift detection of a bright burst
- Swift detection of MXB 0656-072
- GRB 071112C: Optical and NIR data observed with KANATA
- GRB 071112C MITSuME Akeno early optical observation
- GRB 071112C: SARA upper limit
- GRB 071112C : Second Epoch Lulin R-band observations
- GRB071112C MITSuME Okayama Optical Observation
- GRB 071112C: Swift-BAT refined analysis
- GRB 071112C: Swift XRT refined analysis
- GRB 071112C: Optical observations at Crni Vrh
- Swift UVOT upper limits of GRB071112B
- GRB 071112B: Gemini Optical Imaging
- GRB 071112B: Swift-XRT preliminary analysis
- GRB 071112C: Palomar Pre-Imaging
- GRB 071112C : Lulin R-band observation
- GRB 071112C: TAROT Calern observatory optical observations
- Swift XRT follow-up observations of GRB071028B