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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"

21845 results found.

  1. GRB 260909A: SVOM/GRM observation
  2. GRB 260909A: Mondy optical observations and afterglow candidate
  3. GRB 260909A: Xinglong 2.16m optical upper limit
  4. GRB 260909A: SVOM/C-GFT optical upper limit
  5. GRB 260909A: SVOM detection of a burst
  6. GRB 260903A: SAO RAS optical upper limit
  7. GRB 260903A: J-band upper limit with WINTER
  8. GRB 260903A: SVOM/ECLAIRs refined analysis
  9. GRB260903A: Liverpool Telescope optical observations
  10. GRB 260903A: SAO RAS optical observations
  11. EP260903a: EP-WXT detection of a fast X-ray transient
  12. GRB 260903A: OHP/T193 optical afterglow detection
  13. NuSTAR Transient 260828: SOAR Optical Upper Limits
  14. GRB 260903A: LCO optical counterpart detection
  15. GRB 260903A: SVOM detection of a soft faint burst
  16. EP260901a: SVOM/VT optical upper limits
  17. Konus-Wind detection of GRB 260829A
  18. GRB 260829A: SVOM/GRM observation
  19. GRB 260818A: ATCA detection of a candidate radio counterpart
  20. EP260830a: EP-FXT follow-up observation
  21. GRB 260831B / sb26083106: SVOM/GWAC-F60A/B confirmation of optical variation of nova V* GK Per
  22. GRB 260831B / sb26083106: SVOM/VT optical variability of V* GK Per
  23. NuSTAR Transient 260828: LCO Optical Upper Limits
  24. EP260901a: EP-WXT detection of a fast X-ray transient
  25. GRB 260831B: LCO optical upper limits
  26. EP260830a: EP-WXT detection of a fast X-ray transient
  27. GRB 260827A: SVOM/GRM observation
  28. GRB 260831B: SVOM detection of a possible burst
  29. GRB 260825A: SVOM/GRM observation of a long burst
  30. GRB 260818B: Further EP-FXT observation
  31. GRB 260818B: VLT optical and nIR observations
  32. GRB 260818B: TNG NIR observations
  33. GRB 260818B: 6 GHz VLA observations
  34. GRB 260818B: SVOM/VT optical upper limit and continuous observations
  35. GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  36. GRB 260808B: SAO RAS observations of the optical rebrightening
  37. GRB 260822A: SVOM/ECLAIRs refined analysis
  38. GRB 260809A: SVOM/ECLAIRs refined analysis
  39. GRB 260822A: SVOM/VT optical upper limits
  40. IceCube Alert 260825A: Global MASTER-Net observations report
  41. GRB 260822A: PRIME near-infrared upper limits from multiple epochs
  42. GRB 260822A: the candidate optical afterglow is an unrelated type-Ia SN
  43. EP260822a: EP-FXT non-detection and upper limit
  44. GRB 260822A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate
  45. EP260822a: Einstein Probe detection of a fast X-ray transient
  46. GRB 260822A: LCO optical upper limits
  47. GRB 260822A: GROWTH-India Telescope Upper Limits
  48. GRB 260822A: GOTO optical upper limit
  49. GRB 260822A: SVOM detection of a short burst
  50. GRB 260818B: VLA radio observations
  51. GRB 260818B: SVOM/C-GFT optical upper limit
  52. EP260731a: SVOM/ECLAIRs detection through offline targeted search
  53. EP detected a brightening of LMXB 1ES 1735-26.9
  54. GRB260820A: Fermi GBM Final Real-Time Localization
  55. GRB 260818A: J-band observations with WINTER
  56. GRB 260818B: SVOM/ECLAIRs refined analysis
  57. GRB 260818A: SVOM/ECLAIRs refined analysis
  58. GRB 260818B: NOT optical upper limits
  59. GRB 260810A: SVOM/GRM observation
  60. GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  61. GRB 260818B: LCO optical upper limits
  62. EP260806a: SAO RAS multicolor optical observations
  63. GRB 260818A: LCO optical upper limits
  64. EP260812a: AbAO optical upper limit
  65. GRB 260818A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  66. EP260806a: SVOM/ECLAIRs detection through targeted search
  67. EP260806a: NUTTELA-TAO optical observations
  68. EP260812a: AZT-22 optical upper limit
  69. EP260806a: WFST optical observations
  70. EP260812b: Optical upper limit with Kinder
  71. GRB 260805D: SVOM/GRM detection of a possible magnetar burst
  72. GRB 260808B: Liverpool Telescope further optical observations
  73. EP260812a: NOT and Liverpool Telescope upper limits:
  74. EP260812b: Liverpool Telescope observations
  75. EP260812a: refined analysis of the EP-WXT and autonomous EP-FXT observation
  76. EP260812a: SVOM/C-GFT optical upper limit
  77. EP260812b: COLIBRÍ optical observations
  78. EP260812b: SVOM/VT optical observation
  79. GRB 260808A: SVOM/GRM observation
  80. EP260812b: Einstein Probe detection of an X-ray transient
  81. EP trigger #01709278129 (EP260812b?): NOT optical counterpart
  82. GRB 260808B: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical rebrightening
  83. GRB 260810A: AstroSat CZTI detection of a long burst
  84. EP260812a: Einstein Probe detection of an X-ray transient
  85. GRB 260809A: SAO RAS optical observations
  86. GRB 260808B: SAO RAS optical observations
  87. GRB 260317A: SVOM/ECLAIRs detection through offline targeted search and its possible association to magnetar 1E 1841-04.5
  88. EP260806a: MAO/AZT-22 optical observations
  89. GRB260808B: MAO/AZT-22 optical observations
  90. GRB 250607A: SVOM/ECLAIRs detection through offline targeted search
  91. GRB 260809A: J-band upper limit with WINTER
  92. GRB 260805C: CALET Gamma-Ray Burst Monitor detection
  93. GRB 260809A: SVOM/COLIBRÍ (FM-GFT) optical observation
  94. GRB 260808B: SVOM/COLIBRÍ (FM-GFT) optical observation
  95. GRB 260809A: NOT optical observations
  96. GRB260809A: MAO/AZT-22 optical observations
  97. GRB260809A: OHP/T193 optical observations
  98. EP260809a: J-band upper limit with WINTER
  99. GRB 260808B: J-band upper limit with WINTER
  100. GRB 260808B: SVOM/ECLAIRs refined analysis

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