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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"

647 results found.

  1. Konus-Wind detection of GRB 261007A/EP261007a
  2. Konus-Wind detection of GRB 260924A
  3. GRB 260922A: Swift-BAT refined analysis
  4. GRB 260921A: AstroSat CZTI detection
  5. GRB 260921A: Swift-BAT refined analysis
  6. EP260920a: COLIBRÍ optical upper limits
  7. EP Alert 260918.24: Global MASTER-Net observations report
  8. SVOM GRB260918.16: Global MASTER-Net observations report
  9. The EP-WXT trigger 01709306297 is likely the known LMXB 4U 1745-203
  10. The EP-WXT trigger 01709291839 is likely the known LMXB 4U 1745-203
  11. Fermi GRB 260805A: Global MASTER-Net observations report
  12. GRB 260802A / EP J223759.5+531421: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  13. Fermi-LAT Gamma-ray Observations of IceCube-260622A
  14. GRB 260619A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  15. GRB 260616A: SVOM/GRM observation
  16. Fermi GRB 260523A: Global MASTER-Net observations report
  17. EP260509a: Global MASTER-Net observations report
  18. GRB 260421B: VLT/X-shooter spectroscopic redshift z = 2.115
  19. GRB 260321A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  20. Fermi GRB 260221A: Global MASTER-Net observations report
  21. Fermi GRB 260219A: Global MASTER-Net observations report
  22. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  23. EP260209a: Global MASTER-Net observations report
  24. Fermi GRB 260208C: Global MASTER-Net observations report
  25. GRB 260208B: Fermi GBM Detection
  26. GRB 260206A: Swift-XRT observations
  27. GRB 260206A (or XRB from 4U 0513-40): MAXI/GSC detection
  28. Konus-Wind detection of GRB 260128A / EP260128a
  29. Trigger 1442421: Swift detection of HMXB 1A 1118-61
  30. EP260119a: SVOM/VT optical observation
  31. Swift trigger on the HMXB 1A 1118-61
  32. Swift triggered on the HMXB 1A 1118-61
  33. IceCube Alert 260111A: Global MASTER-Net observations report
  34. Swift GRB 251214B: Global MASTER-Net observations report
  35. SVOM GRB251211.12: Global MASTER-Net observations report
  36. GRB 251208A: SVOM/GRM observation of a short burst
  37. Fermi GRB 251127A: Global MASTER-Net observations report
  38. Fermi trigger No 784279167: Global MASTER-Net observations report
  39. GRB 251103A: NOT spectroscopic redshift z = 0.76
  40. Fermi GRB 251013A: Global MASTER-Net observations report
  41. GRB 250909A: AstroSat CZTI detection
  42. SVOM/sb25090605: detection of an X-ray transient from the LMXB 4U 0513-40
  43. EP250901a: Mondy, Assy and SAO RAS optical limits
  44. GRB 250831A (SVOM trigger sb25083102): KAIT confirmation of stellar flare
  45. GRB 250831A (SVOM trigger sb25083102): confirmation of a stellar flare by SVOM/VT
  46. GRB 250831A (SVOM trigger sb25083102) is likely an outburst from star G 272-61
  47. GRB 250831A: Swift-XRT counterpart detection
  48. GRB 250831A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  49. GRB 250831A: SVOM/VT upper limit with VHF data
  50. sb25081602: Swift-XRT observations
  51. SVOM/sb25081602: detection of a likely X-ray transient
  52. The SVOM alert sb25072103 is not due to a GRB, but to a new galactic transient SVOM J195836+32283.
  53. EP250711a: COLIBRÍ continuous optical observations
  54. IceCube-250708A: Global MASTER-Net observations report
  55. EP250610a: Global MASTER-Net observations report
  56. GRB 250516A: Swift-BAT refined analysis
  57. MAXI GRB250515.65: Global MASTER-Net observations report
  58. GRB 250430A: Swift-BAT refined analysis
  59. Fermi GRB 250502B: Global MASTER-Net observations report
  60. Fermi-LAT gamma-ray observations of IceCube-250421A
  61. GRB 250327A: Swift-XRT refined Analysis
  62. GRB 250327A: SVOM/VT optical candidate
  63. GRB 250322A: AstroSat CZTI detection of a short burst
  64. Fermi trigger No 763509110: Global MASTER-Net observations report
  65. Fermi GRB 250309B: Global MASTER-Net observations report
  66. GRB 250226A: Fermi GBM Observation
  67. Fermi GRB 250223A: Global MASTER-Net observations report
  68. GRB 250211A: SVOM trigger sb25021103 is not a GRB
  69. LIGO/Virgo/KAGRA S250206dm: Kinder confirmation of a possible artefact in AT 2025bbo
  70. LIGO/Virgo/KAGRA S250206dm: Global MASTER-Net observations report
  71. LIGO/Virgo/KAGRA S250206dm: Optical observations of candidate AT 2025bbo with Kinder
  72. GRB 250207A: REM IR afterglow detection
  73. GRB 250207A: REM optical afterglow detection
  74. GRB 250114B: OHP/T193 optical upper limit
  75. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  76. GRB 241207C: MASTER optical observations
  77. Fermi trigger No 755225799: Global MASTER-Net observations report
  78. Swift GRB 241128A: Global MASTER-Net observations report
  79. Swift GRB241127.91: Global MASTER-Net observations report
  80. GRB 241113A: Swift/UVOT Detection
  81. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  82. Fermi GRB 240918A: Global MASTER-Net observations report
  83. EP EP240913a: Global MASTER-Net observations report
  84. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  85. GRB 240829A: Swift-BAT refined analysis
  86. LAT GRB240828.62: Global MASTER-Net observations report
  87. Fermi trigger No 745866488: Global MASTER-Net observations report
  88. Fermi trigger No 745057312: Global MASTER-Net observations report
  89. Swift GRB 240811A: Global MASTER-Net observations report
  90. GRB 240727C: AstroSat CZTI detection of a long burst
  91. Konus-Wind detection of GRB 240627A
  92. Fermi GRB 240702A: Global MASTER-Net observations report
  93. Fermi trigger No 741211696: Global MASTER-Net observations report
  94. Swift Trigger 1232465: consistent with noise
  95. Konus-Wind detection of GRB 240529A
  96. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  97. GRB 240419B: Swift-BAT refined analysis
  98. LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
  99. LIGO/Virgo/KAGRA S240422ed: WINTER J-band upper limits on the Swift/XRT source S240422ed_X61
  100. LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam upper limits on the Swift/XRT source S240422ed_X61

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