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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').
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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"

41916 results found.

  1. EP251118a: Global MASTER-Net observations report
  2. EP251118a: preliminary result of EP-FXT follow-up observation
  3. LAT GRB251118.86: Global MASTER-Net observations report
  4. GRB 251118A: Fermi-LAT detection
  5. EP251118a: NOT candidate optical counterpart
  6. GRB 251118A: Swift ToO observations
  7. EP251118a: Einstein Probe detected of a fast X-ray transient
  8. Fermi GRB 251118B: Global MASTER-Net observations report
  9. GRB 251118B: Fermi GBM Final Real-time Localization
  10. LIGO/Virgo/KAGRA S251112cm: Upper limits from Glowbug gamma-ray observations
  11. GRB 251118A: BALROG localization (Fermi Trigger 785190695 / GRB 251118855)
  12. GRB 251117A: FTW Observations of Swift candidate X-ray sources
  13. GRB 251118A: Fermi GBM Final Real-time Localization
  14. GRB 251116C: SVOM/ECLAIRs refined analysis
  15. GRB 251116B: SVOM/ECLAIRs refined analysis
  16. GRB 251117A: AstroSat CZTI detection
  17. GRB 251114B: Insight-HXMT/HE detection
  18. GRB 251114B: GECAM-B detection of a short burst
  19. GRB 251117A: Fermi GBM observation
  20. GRB 251013C: Koshka, SAO RAS, Mondy, and CrAO optical observations, possible SN detection
  21. GRB 251116D: Insight-HXMT/HE detection
  22. GRB 251115A: Swift-XRT observations
  23. GRB 251117A: Swift/BAT-GUANO localization skymap of a short burst
  24. GRB 251117A: SVOM/GRM observation of a short burst
  25. GRB 251117A: Tiled Swift observations
  26. GRB 251117A: Fermi-LAT detection
  27. LAT GRB251117.51: Global MASTER-Net observations report
  28. LIGO/Virgo/KAGRA S251117dq: Identification of a GW compact binary merger candidate
  29. GRB 251116C: Swift/BAT arcminute localization of a burst
  30. LIGO/Virgo/KAGRA S251112cm: J-GEM follow-up observations
  31. LIGO/Virgo/KAGRA S251112cm: Classification of reported candidates with SOAR/Goodman
  32. GRB 251116B: SVOM/VT optical upper limit
  33. LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
  34. GRB 251116C: Swift-XRT observations
  35. GRB 251117A: Fermi GBM Final Localization Correction
  36. GRB 251116D: Glowbug gamma-ray detection
  37. EP251023a: Assy AZT-20 optical observations
  38. EP251023a: UAFO and AbAO optical observations
  39. GRB 251116D: AstroSat CZTI detection
  40. LIGO/Virgo/KAGRA S251112cm: EP-FXT follow-up observations
  41. The EP-WXT trigger 01709247588: more evidence of flaring star from Mondy optical observations
  42. GRB 251116C: SVOM/VT optical upper limit
  43. GRB 251025B: further Mondy optical observations
  44. GRB 251111A: Mondy optical upper limit
  45. GRB 251116B: EP-FXT follow-up observation
  46. LIGO/Virgo/KAGRA S251116en: Identification of a GW compact binary merger candidate
  47. LIGO/Virgo/KAGRA S251112cm: Observations with the NSF-DOE Vera C. Rubin Observatory
  48. GRB 251116B: LCO optical upper limits
  49. GRB 251116C: LCO optical upper limits
  50. SVOM GRB251116C: Global MASTER-Net observations report
  51. GRB 251116C: SVOM detection of a burst
  52. GRB 251116B: SVOM detection of a burst
  53. IceCube-Cascade 251112A: Upper limits from a search for additional neutrino events in IceCube
  54. GRB 251116A: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo/KAGRA S251112cm: GRANDMA observations of the skymap
  56. LIGO/Virgo/KAGRA S251112cm: AT2025adht follow-up at Maidanak observatory by GRANDMA
  57. GRB 251115A: Tiled Swift observations
  58. GRB 251115A: Fermi-LAT detection
  59. GRB 251013C: joint SVOM/ECLAIRs-GRM refined analysis
  60. Fermi GRB 251115A: Global MASTER-Net observations report
  61. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 4-Update Localization Volume
  62. GRB 251115A: Fermi GBM Final Real-time Localization
  63. LIGO/Virgo/KAGRA S251112cm: DECam GW-MMADS candidates
  64. LIGO/Virgo/KAGRA S251112cm: Updated Sky localization and false alarm rate estimate
  65. GRB 251113A: Glowbug gamma-ray detection
  66. GRB 251113A: AstroSat CZTI detection
  67. GRB 251114B: Fermi GBM Final Real-time Localization
  68. GRB 251112A: Swift-BAT refined analysis
  69. Konus-Wind detection of GRB 251108C
  70. Fermi trigger No 784717756: Global MASTER-Net observations report
  71. Konus-Wind detection of GRB 251103A
  72. LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
  73. LIGO/Virgo/KAGRA S251112cm: Swift XRT observations, 20 X-ray sources
  74. The EP-WXT trigger 01709248221 is likely a flaring star
  75. Fermi GRB 251114A: Global MASTER-Net observations report
  76. LIGO/Virgo/KAGRA S251112cm: Candidates from the Zwicky Transient Facility
  77. GRB 251114A: Fermi GBM Final Real-time Localization
  78. LIGO/Virgo/KAGRA S251112cm: FTW observations of galaxies within localization region
  79. Fermi GRB 251113A: Global MASTER-Net observations report
  80. GRB 251113A: BALROG localization (Fermi Trigger 784748255 / GRB 251113734)
  81. GRB 251113A: Fermi GBM Final Real-time Localization
  82. GRB 251111A: SVOM/ECLAIRs refined analysis
  83. GRB 251025B: SVOM/ECLAIRs refined analysis
  84. GRB 251112A: Swift/UVOT Upper Limits
  85. LIGO/Virgo/KAGRA S251112cm: ATLAS pre-detections of AT2025adgp and AT2025adgq
  86. GRB 251112A: Swift-XRT refined Analysis
  87. GRB 251108C: AstroSat CZTI detection
  88. LIGO/Virgo/KAGRA S251112cm: Detection of two young transients by BlackGEM/MeerLICHT: AT2025adgp and AT2025adgq
  89. GRB 251112B: MAXI/GSC detection
  90. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  91. LIGO/Virgo/KAGRA S251112cm: Initial GOTO-South observations
  92. GRB 251108B: Glowbug gamma-ray detection
  93. Swift Trigger 1413695: a possible GRB 251112A
  94. LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
  95. Fermi trigger No 784621743: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 3-Initial Localization Volume
  97. GRB251111A: 1.3m DFOT optical upper limit
  98. LIGO/Virgo/KAGRA S251112cm: Identification of a GW compact binary merger candidate
  99. GRB 251106B: Glowbug gamma-ray detection of a likely short burst
  100. GRB 251111A: Swift-XRT afterglow detection

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