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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"

23727 results found.

  1. Fermi GRB 240511A: Global MASTER-Net observations report
  2. Swift GRB 240511A: Global MASTER-Net observations report
  3. Fermi trigger No 737105243: Global MASTER-Net observations report
  4. Fermi trigger No 737152719: Global MASTER-Net observations report
  5. GRB 240511A: Swift detection of a burst
  6. Fermi trigger No 737102480: Global MASTER-Net observations report
  7. Fermi trigger No 737111207: Global MASTER-Net observations report
  8. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  9. Fermi trigger No 736967879: Global MASTER-Net observations report
  10. EP240506a: Xinglong optical upper limit
  11. EP240506a: Archival radio searching
  12. EP240506a: TRT optical upper limit
  13. EP240506a: BOOTES Network optical upper limit
  14. Fermi trigger No 736733320: Global MASTER-Net observations report
  15. EP240506a: Optical upper limit with Kinder observations
  16. IPN triangulation of GRB 240504A
  17. EP240506a: EP-WXT detection of a new fast X-ray transient
  18. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  20. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  21. Fermi trigger No 736564880: Global MASTER-Net observations report
  22. LIGO/Virgo/KAGRA S240505av: Identification of a GW compact binary merger candidate
  23. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  24. Fermi trigger No 736461232: Global MASTER-Net observations report
  25. Fermi GRB 240504A: Global MASTER-Net observations report
  26. Fermi trigger No 736472503: Global MASTER-Net observations report
  27. GRB 240503A: AstroSat CZTI detection
  28. Fermi trigger No 736387941: Global MASTER-Net observations report
  29. GRB 240502A: GOTO optical upper limit
  30. Fermi trigger No 736379109: Global MASTER-Net observations report
  31. GRB 240502C: GOTO possible optical counterpart candidates
  32. Fermi GRB 240502B: Global MASTER-Net observations report
  33. Fermi GRB 240502A: Global MASTER-Net observations report
  34. GRB 240501B: GRBAlpha detection
  35. GRB 240430A: GRBAlpha detection
  36. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  37. Integral GRB240502.23: Global MASTER-Net observations report
  38. Fermi GRB 240501A: Global MASTER-Net observations report
  39. Fermi trigger No 736197684: Global MASTER-Net observations report
  40. GRB 240426A: VZLUSAT-2 detection
  41. GRB 240425A: VZLUSAT-2 detection
  42. GRB 240501B: AstroSat CZTI detection
  43. GRB 240408B: VZLUSAT-2 detection
  44. GRB 240407A: VZLUSAT-2 detection
  45. LIGO/Virgo/KAGRA S240501an: Identification of a GW compact binary merger candidate
  46. GRB 240425A: GRBAlpha detection
  47. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet ToO observations
  48. Fermi GRB 240428A: Global MASTER-Net observations report
  49. LIGO/Virgo/KAGRA S240422ed: DDOTI Optical Upper Limit for J-GEM24a
  50. LIGO/Virgo/KAGRA S240422ed: Observations with 1.6m Mephisto
  51. LIGO/Virgo S240422ed: Swift XRT observation of EP240426a
  52. LIGO/Virgo/KAGRA S240422ed: NOT optical observations of EP240426a
  53. EP240426b: EP-WXT detection of a new fast X-ray transient
  54. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfq, AT2024hfr, AT2024hfs, and AT2024hfx
  55. LIGO/Virgo/KAGRA S240422ed: BOOTES-6/DPRT optical upper limits for EP240426a
  56. LIGO/Virgo/KAGRA S240422ed: GRANDMA Optical Upper Limits for EP240426a
  57. GRB 240426A: AstroSat CZTI detection
  58. LIGO/Virgo/KAGRA S240422ed: BOOTES-4/MET Optical Upper Limits for EP240426a
  59. LIGO/Virgo/KAGRA S240422ed: EP-FXT Detection of the Potential Opitcal Electromagnetic Counterpart AT 2024hfq Reported by DECam
  60. GRB 240414A: NOEMA detection
  61. LIGO/Virgo/KAGRA S240422ed: Continued Magellan Observations
  62. EP240426a: GMG optical upper limit
  63. LVK S240422ed: Further Swift-XRT followup of three sources
  64. LIGO/Virgo/KAGRA S240422ed: EP-FXT detection of a candidate counterpart EP240426a
  65. LIGO/Virgo/KAGRA S240426s: Identification of a GW compact binary merger candidate
  66. LIGO/Virgo/KAGRA S240422ed: Magellan Follow-up Observations of Swift/XRT candidates
  67. LIGO/Virgo/KAGRA S240422ed: Zwicky Transient Facility contuinued observations of S240422ed and candidate analysis
  68. LIGO/Virgo/KAGRA S240422ed: GOTO counterpart search update and AT2024hfx, AT2024hgl observations
  69. LIGO/Virgo/KAGRA S240422ed: Second night Pan-STARRS observations of the skymap
  70. LIGO/Virgo/KAGRA S240422ed: Further near-infrared observations with Subaru/MOIRCS by J-GEM Collaboration
  71. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-FXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  72. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA and Kilonova-Catcher galaxy targeting observations
  73. LIGO/Virgo/KAGRA S240422ed: Magellan Spectrum of GW-MMADS Candidate AT2024hdo Indicates a Type II SN
  74. Fermi trigger No 735697285: Global MASTER-Net observations report
  75. GRB 240419B: Swift-BAT refined analysis
  76. GRB 240421B: Swift-BAT refined analysis
  77. GRB 240422A: Glowbug gamma-ray detection
  78. LIGO/Virgo/KAGRA S240422ed: Archival BlackGEM/MeerLICHT detections of AT 2024hdr & AT 2024hdq
  79. LIGO/Virgo/KAGRA S240422ed: No significant counterpart candidates in HAWC observations
  80. LIGO/Virgo/KAGRA S240422ed: No significant candidates in GRANDMA/FRAM Observations
  81. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  82. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  83. LIGO/Virgo/KAGRA S240422ed: Early X-ray Upper Limits from EP-WXT for the LVK Sky Localization Region
  84. LIGO/Virgo/KAGRA S240422ed: Continued Imaging of Mag24a
  85. LIGO/Virgo/KAGRA S240422ed: Potential Magellan candidates from GCN 36263 are unrelated.
  86. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Three Potential Electromagnetic Counterparts Reported So Far
  87. GRB 240421B: GRBAlpha detection
  88. IceCube Alert 240424.08: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S240422ed: Magellan Detection of a Potential Electromagnetic Counterpart
  90. LIGO/Virgo/KAGRA S240422ed: Subaru/MOIRCS near-infrared observations by J-GEM Collaboration
  91. LIGO/Virgo/KAGRA S240422ed: Potential Candidates from Magellan galaxy-based search
  92. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from Pan-STARRS observations of the skymap
  93. LIGO/Virgo/KAGRA S240422ed: GOTO counterpart search
  94. LIGO/Virgo/KAGRA S240422ed: No Counterparts in DDOTI/OAN Optical Observations
  95. GRB 240419A: Swift-BAT refined analysis
  96. GRB 240418A: Swift-BAT refined analysis
  97. LXT240402A/GRB240402B: Chandra X-ray detection
  98. LIGO/Virgo/KAGRA S240422ed: no candidate counterparts from ATLAS observations
  99. LIGO/Virgo/KAGRA S240422ed: WINTER near-infrared J-band observations
  100. LIGO/Virgo/KAGRA S240422ed: Magellan Observations

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