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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.

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').
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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21798 results found.

  1. GRB 251117A: Fermi-LAT detection
  2. LIGO/Virgo/KAGRA S251117dq: Identification of a GW compact binary merger candidate
  3. LIGO/Virgo/KAGRA S251112cm: J-GEM follow-up observations
  4. LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
  5. EP251023a: Assy AZT-20 optical observations
  6. EP251023a: UAFO and AbAO optical observations
  7. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  8. GRB 251025B: further Mondy optical observations
  9. GRB 251111A: Mondy optical upper limit
  10. LIGO/Virgo/KAGRA S251116en: Identification of a GW compact binary merger candidate
  11. LIGO/Virgo/KAGRA S251112cm: Observations with the NSF-DOE Vera C. Rubin Observatory
  12. GRB 251116B: LCO optical upper limits
  13. GRB 251116C: LCO optical upper limits
  14. GRB 251116C: SVOM detection of a burst
  15. LIGO/Virgo/KAGRA S251112cm: GRANDMA observations of the skymap
  16. GRB 251115A: Fermi-LAT detection
  17. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  18. LIGO/Virgo/KAGRA S251112cm: DECam GW-MMADS candidates
  19. GRB 251113A: AstroSat CZTI detection
  20. Konus-Wind detection of GRB 251108C
  21. LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
  22. IPN triangulation of GRB 251108C
  23. LIGO/Virgo/KAGRA S251112cm: FTW observations of galaxies within localization region
  24. GRB 251111A: SVOM/ECLAIRs refined analysis
  25. GRB 251025B: SVOM/ECLAIRs refined analysis
  26. GRB 251112A: Swift/UVOT Upper Limits
  27. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo/KAGRA S251112cm: Initial GOTO-South observations
  29. Swift Trigger 1413695: a possible GRB 251112A
  30. GRB251111A: 1.3m DFOT optical upper limit
  31. LIGO/Virgo/KAGRA S251112cm: Identification of a GW compact binary merger candidate
  32. GRB 251111A: Swift-XRT afterglow detection
  33. GRB 251111A: SVOM/VT optical observations with X-band data
  34. GRB 251111A: SVOM/VT optical observations with VHF data
  35. GRB 251111A: LCO optical observation
  36. GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
  37. GRB 251111A: SVOM detection of a soft burst
  38. GRB 251106A: Swift/UVOT Upper Limits
  39. LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
  40. GRB 251105A: AstroSat CZTI detection
  41. LIGO/Virgo/KAGRA S251108fi: Identification of a GW compact binary merger candidate
  42. GRB 251102B: SVOM/GRM observation
  43. LIGO/Virgo/KAGRA S251108dn: Identification of a GW compact binary merger candidate
  44. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
  45. GRB 251106A: Swift-XRT afterglow detection
  46. GRB 251106A: Kilonova-Catcher optical upper limit
  47. Fermi GBM Sub-Threshold Detection of GRB 251106A
  48. GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
  49. GRB 251106A: MASTER optical observations
  50. EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
  51. GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
  52. GRB 251104A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  53. GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
  54. GRB 251103B: Swift/UVOT Upper Limits
  55. LIGO/Virgo/KAGRA S251105aj: Identification of a GW compact binary merger candidate
  56. GRB 251105A: Fermi GBM Final Real-time Localization
  57. GRB 251103B: Fermi GBM observation
  58. GRB 251104A: SVOM detection of a burst
  59. GRB 251103A: WFST optical observations
  60. EP251102a: OHP/T193 optical observations
  61. GRB 251103A: OHP/T193 optical observations
  62. GRB 251103A: Xinglong 2.16m optical detection
  63. GRB 251103A: KAIT optical observations
  64. GRB 251103B: Nanshan/HMT optical upper limit
  65. GRB 251013C: 7DT detection and Medium-band SED of Afterglow
  66. GRB 251103A: Swift/BAT-GUANO arcminute localization of a burst
  67. GRB 251103B: MITSuME Akeno optical upper limits
  68. LIGO/Virgo/KAGRA S251103f: Identification of a GW compact binary merger candidate
  69. EP251102a: NIR observations with WINTER
  70. GRB 251103A: J-band detection with WINTER
  71. GRB 251103B: GROWTH-India Telescope optical upper limits
  72. GRB 251103A: Kilonova-Catcher optical afterglow detection
  73. GRB 251103B: Enhanced Swift-XRT position
  74. GRB 251103B: Swift detection of a burst
  75. GRB 251103A: Swift/UVOT Detection
  76. GRB 251103A: Swift-XRT afterglow detection
  77. GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
  78. EP251102a: Einstein Probe detection of a fast X-ray transient
  79. GRB 251025B: OHP/T193 optical upper limit
  80. EP251102a (WXT 11900459650): LCO observations confirm COLIBRÍ candidate
  81. GRB 251103A: LCO optical observation
  82. EP251102.890: COLIBRÍ optical counterpart candidate
  83. GRB 251102A: AstroSat CZTI detection
  84. GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart
  85. GRB 251103A: LCO optical afterglow detection
  86. GRB 251103A: NOT optical afterglow candidate
  87. LIGO/Virgo/KAGRA S251031cq: Identification of a GW compact binary merger candidate
  88. GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
  89. Konus-Wind detection of GRB 251028A
  90. GRB 251025C: SVOM/GRM observation
  91. GRB 251028A: GECAM-B detection
  92. GRB 251028A: SVOM/GRM observation
  93. GRB 251022A: Swift-XRT confirmation of fading
  94. GRB 250926B: VZLUSAT-2 detection
  95. GRB 250926A: VZLUSAT-2 detection
  96. GRB 250925A: VZLUSAT-2 detection
  97. GRB 251026A/EP251026a: SVOM/VT optical counterpart
  98. GRB 251028B: Swift/BAT-GUANO localization skymap of a burst
  99. GRB 251025B: GROWTH-India Telescope continued multiband optical observations and rebrightening
  100. GRB251026B: PRIME H-band upper limit

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