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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"

12170 results found.

  1. SVOM J195836+32283/sb25072103: NIR observations with WINTER
  2. GRB 250717B: SVOM/GRM observation
  3. The SVOM alert sb25072103 is not due to a GRB, but to a new galactic transient SVOM J195836+32283.
  4. GRB 250721A: MAXI/GSC detection
  5. GRB 250720B: Fermi GBM Final Localization Correction
  6. GRB 250720A: Fermi GBM Final Localization
  7. Fermi trigger No 774730635: Global MASTER-Net observations report
  8. Fermi Gamma-ray Burst Monitor trigger 774670514/250720094 is not a GRB
  9. LIGO/Virgo/KAGRA S250711q: Upper limits from Swift/BAT-GUANO
  10. GRB 270713A: Kitab and AbAO Optical Observations
  11. Konus-Wind detection of GRB 250716A
  12. GRB 250716A: Swift-XRT afterglow detection
  13. Fermi GRB 250716A: Global MASTER-Net observations report
  14. GRB 250713A: SVOM/C-GFT upper limit
  15. GRB 250713A: Swift-XRT observations
  16. EP250711a: EP-WXT detection and FXT follow-up observation of a fast X-ray transient
  17. Fermi GRB 250711A: Global MASTER-Net observations report
  18. EP250702a: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  19. LIGO/Virgo/KAGRA S250711q: Identification of a GW compact binary merger candidate
  20. GRB 250702B,D,E/EP250702A: JCMT sub-mm observations at 350 GHz
  21. LIGO/Virgo/KAGRA S250629bs: Upper limits from Swift/BAT-GUANO
  22. LIGO/Virgo/KAGRA S250629ae: Upper limits from Swift/BAT-GUANO
  23. LIGO/Virgo/KAGRA S250704ab: NED Galaxies in the 4-Update Localization Volume
  24. GRB 250704B / EP250704a: VLA radio detection
  25. GRB 250706B/C: Konus-Wind analysis of the prompt emission
  26. GRB 250704B / EP250704a: Mondy and AbAO optical observations
  27. Fermi-LAT Gamma-ray Observations of IceCube-250706A
  28. GRB 250706B/C: Fermi-LAT detection
  29. IceCube-250706A: Global MASTER-Net observations report
  30. EP250702a/ GRB 250702B: NuSTAR X-ray Observations
  31. GRB 250706C: Konus-Wind detection of a very bright GRB ~1200 s before GRB 250706B
  32. GRB 250704A: Swift/BAT-GUANO localization skymap of a burst
  33. GRB 250706B: refined SVOM/MXT data analysis
  34. GRB 250706A: SAO RAS optical observations
  35. GRB250706B: Swift-XRT counterpart detection
  36. GRB 250706B: iTelescope optical observations
  37. GRB 250706B: SVOM detection of a long burst
  38. GRBs 250702B,C,D,E / EP250702a: J band upper limit by SYSU 80cm infrared telescope
  39. EP250702a/GRB 250702B,C,D,E: Archival radio observations from ASKAP VAST
  40. Konus-Wind detection of GRB 250703A
  41. EP250704a/GRB 250704B: GSP observations of the optical counterpart
  42. Konus-Wind detection of short/hard GRB 250704B/ EP250704a
  43. EP250704a/GRB 250704B VLT/HAWK-I NIR afterglow detection
  44. LIGO/Virgo/KAGRA S250704ab: NED Galaxies in the 3-Initial Localization Volume
  45. EP250704a: refined analysis of the EP-WXT and FXT follow-up observations
  46. EP250704a / GRB250704B: Swift-XRT counterpart detection
  47. GRB 250704A: Swift-XRT afterglow detection
  48. Konus-Wind detection of GRB 250702F
  49. EP250704a: COLIBRÍ optical counterpart candidate
  50. EP250704a: Einstein Probe detection of an X-ray transient
  51. LIGO/Virgo/KAGRA S250704ab: Coverage and upper limits from MAXI/GSC observations
  52. GRB 250704A: SVOM detection of a burst
  53. Fermi GRB 250703A: Global MASTER-Net observations report
  54. GRB 250702F: Swift-XRT refined Analysis
  55. GRBs 250702B,C,D,E / EP250702a: VLT/HAWK-I NIR candidate
  56. GRBs 250702B,C,D,E / EP250702a: SVOM/GRM observation
  57. GRBs 250702B,C,D,E / EP250702a: Konus-Wind detection of a hard X-ray transient activity
  58. EP250702a: Global MASTER-Net observations report
  59. EP250702a : an X-ray transient detected by Einstein Probe likely associated with GRB 250702B,C,D,E
  60. Fermi GRB 250702C: Global MASTER-Net observations report
  61. Konus-Wind detection of GRB 250627A
  62. LIGO/Virgo/KAGRA S250701bp: Identification of a GW compact binary merger candidate
  63. Fermi Gamma-ray Burst Monitor trigger 772838080/250628885 is not a GRB
  64. GRB 250628B: Swift-XRT observations
  65. GRB 250628A: REM optical/NIR upper limits
  66. GRB 250628B: SVOM detection of a long burst
  67. GRB 250628A: Swift-XRT refined Analysis
  68. Fermi GRB 250626A: Global MASTER-Net observations report
  69. GRB 250628A: Swift detection of a burst
  70. GRB 250625A: Leavitt Observatory afterglow detection
  71. GRB 250625A: ABObservatory afterglow detection
  72. GRB 250625A: OHP/T193 optical detection
  73. GRB 250625A: Fermi-LAT detection
  74. GRB 250625A: Swift-XRT refined Analysis
  75. Swift GRB 250625A: Global MASTER-Net observations report
  76. GRB 250620B: Fermi GBM Observation
  77. GRB 250625A: SAO RAS possible optical afterglow
  78. Fermi GRB 250625A: Global MASTER-Net observations report
  79. GRB 250625A: Swift detection of a burst
  80. GRB 250620A: AstroSat CZTI detection
  81. The EP-WXT trigger 01709179396 is likely a flaring star CSTAR 38580
  82. GRB 241018A: Maidanak optical observations
  83. GRB 250620C: AstroSat CZTI detection
  84. sb25061207/GRB 250612D - SVOM/ECLAIRs refined analysis
  85. Fermi GRB 250623A: Global MASTER-Net observations report
  86. Fermi trigger No 772190032: Global MASTER-Net observations report
  87. Konus-Wind detection of GRB 250620C
  88. GRB 250621B: SVOM/GRM detection of a possible magnetar X-ray burst
  89. GRB250620A: Fermi GBM Observation
  90. Fermi GRB 250621A: Global MASTER-Net observations report
  91. GRB 250620B: Swift/BAT-GUANO localization skymap of a burst
  92. GRB250620C: Fermi GBM Observation
  93. GRB 250620A: Swift/BAT-GUANO subthreshold detection of a possibly short burst
  94. GRB 250619B: Swift/BAT-GUANO localization skymap of a burst
  95. GRB 250620C: Fermi GBM Final Real-time Localization
  96. Fermi trigger No 772128434: Global MASTER-Net observations report
  97. GRB 250620B: Fermi GBM Final Real-time Localization
  98. GRB 250620A: Fermi GBM Final Real-time Localization
  99. Fermi trigger No 772058337: Global MASTER-Net observations report
  100. Fermi Gamma-ray Burst Monitor trigger 772058337/250619860 is not a GRB

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