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"32485 results found.
- LIGO/Virgo/KAGRA S241114y: Updated Sky localization
- Fermi GRB 241118A: Global MASTER-Net observations report
- Updates to IceCube realtime alert system for muon tracks
- GRB 241117A: SVOM/GRM observation of a short burst with extended emission
- Fermi GRB 241117B: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
- GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
- Fermi GRB 241117A: Global MASTER-Net observations report
- GRB 241115C: Fermi GBM Observation
- LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
- EP241115a/GRB 241115D: Optical upper limits with Kinder observations
- GRB 241115A: Mephisto upper limits
- GRB 241113B: Mephisto upper limits
- EP241115a/GRB 241115D: Swift/XRT follow-up observation
- GRB 241115D / EP 241115a: SVOM/GRM observation
- The EP-WXT trigger 01709120856 is likely a flaring star
- EP241113a: Swift XRT weak detection
- GRB 241115A: Fermi GBM Observation
- GRB 241115A: LCOGT Optical Upper Limits
- Fermi GRB 241115B: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
- EP241115a: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S241113p: Updated Sky localization
- EP241113a: No Detection in Fermi-GBM Observations
- Swift GRB 241115A: Global MASTER-Net observations report
- Fermi GRB 241115A: Global MASTER-Net observations report
- EP 241113a: LBT possible optical counterpart
- GRB 241113B: KAIT Optical Afterglow Candidate
- LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
- GRB 241113A: Swift-BAT refined analysis
- LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
- GRB 241113A: PRIME near-infrared upper limits
- Fermi GRB 241114A: Global MASTER-Net observations report
- EP241113a: Global MASTER-Net observations report
- GRB 241113B: J-band upper limit from WINTER
- GRB 241113A: J-band observations with WINTER
- EP241113a : J-band observations with WINTER
- GRB 241030A: LCO optical observation
- IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
- GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
- GRB 241113A: KAIT optical observations
- EP241113b: Global MASTER-Net observations report
- EP241113b/GRB 241113B: EP detection of GRB 241113B
- Fermi-LAT gamma-ray observations of IceCube-241113A
- GRB 241113B: SVOM/GRM observation
- LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
- EP241107a: SOAR upper limits
- GRB 241113A: Swift/UVOT Detection
- GRB 241113A: REM detection of the optical/NIR afterglow
- Konus-Wind detection of GRB 241107A (short/hard)
- LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
- GRB 241113B: Swift ToO observations
- GRB 241113A: LCO optical observations
- GRB 241112B: GMG Optical Upper Limit
- GRB241113A: LCOGT (40-cm) optical counterpart detection
- GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
- SVOM/GRM detection of a short burst from SGR 1E1841-045
- LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
- GRB 241105A: ATCA Radio Upper Limits
- GRB 241112B: AbAO optical upper limit
- GRB 241107A: GROWTH-India telescope optical upper limit
- Fermi GRB 241112A: Global MASTER-Net observations report
- Fermi-GBM Sub-Threshold Detection of GRB 241112B
- GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
- GRB 241112B: LCO optical detection of the SVOM/VT candidate
- GRB 241112B: SVOM/GRM observation
- GRB 241112B: SVOM/VT afterglow detection
- Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
- GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
- GRB 241112B: Mephisto optical upper limits
- GRB 241112B: GOTO optical upper limits
- GRB 241112B: Swift ToO observations
- GRB 241107A: INTEGRAL IBIS localization
- EP241107a: EP-FXT follow-up observations
- LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
- GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
- LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
- IPN triangulation of GRB 241107A (short/hard)
- GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
- GRB 241025C: VZLUSAT-2 detection
- GRB 241025A: VZLUSAT-2 detection
- GRB 241018A: cubesat Avion detection
- GRB 241030B: TESS detection of optical counterpart
- LIGO/Virgo/KAGRA S241110br: Updated Sky localization
- LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
- LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
- LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
- EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
- LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
- EP241107a: AbAO optical upper limit
- LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
- GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
- LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
- LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
- EP241109a: confirmation of a stellar flare by BOOTES-7
- LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
- EP241107A: MASTER optical observations of xray transient
- EP241107a: KAIT optical observations
- GRB 241108A: Swift ToO observations
- GRB 241030A: TESS observations