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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. EP250111a: Global MASTER-Net observations report
  2. EP250108a / AT 2025kg (the "kangaroo”): VLT/X-shooter spectroscopic redshift z = 0.176 and LFBOT classification
  3. EP250111a: a new X-ray transient detected by Einstein Probe
  4. GRB 250109A / EP250109A: Swift/BAT-GUANO localization skymap of a burst
  5. Konus-Wind detection of GRB 250107C
  6. EP250109a / GRB 250109A: refined EP-WXT analysis and EP-FXT follow-up observation
  7. Konus-Wind detection of GRB 250107D (short/hard)
  8. IPN triangulation of GRB 250107D (short/hard)
  9. EP250109a: EP-WXT detection of an X-ray transient
  10. EP250108a: EP-WXT detection of an X-ray transient
  11. GRB 250108B: Swift-XRT refined Analysis
  12. Swift GRB 250108B: Global MASTER-Net observations report
  13. Fermi Gamma-ray Burst Monitor trigger 758061038/250108855 is not a GRB
  14. GRB 250103A: Swift-XRT afterglow detection
  15. GRB 250108B: Swift detection of a burst
  16. GRB 241228B: Fermi-LAT detection
  17. GRB 250101A: J band upper limit by SYSU 80cm telescope
  18. The EP-WXT trigger 01709129925 is likely a flaring star
  19. Fermi trigger No 757753930: Global MASTER-Net observations report
  20. GRB 250103B: Swift-XRT refined Analysis
  21. GRB 250103A: Bassano Bresciano Observatory upper limit
  22. IceCube-250101A: Upper limits from a search for additional neutrino events in IceCube
  23. IceCube Alert 250102.58: Global MASTER-Net observations report
  24. GRB 250103A: SVOM detection of a long burst (duplicate submission)
  25. GRB 250103A: SVOM detection of a long burst
  26. LIGO/Virgo/KAGRA S241230bd: Upper limits from Swift/BAT-GUANO
  27. GRB 250101A: further SAO RAS optical observations
  28. GRB 250101A: SAO RAS optical observations
  29. Swift GRB250101.56: Global MASTER-Net observations report
  30. GRB 241217a/EP241217b: ATCA Radio Detection
  31. EP241217a: VLA Radio Detection

  32. LIGO/Virgo/KAGRA S241231du: Coverage and upper limit from MAXI/GSC observations
  33. LIGO/Virgo/KAGRA S241231bg: Updated NED Galaxies in the Localization Volume
  34. LIGO/Virgo/KAGRA S241231bg: NED Galaxies in the Localization Volume
  35. GRB 241229A: EP-FXT X-ray afterglow confirmation
  36. EP241217A: J band upper limit by SYSU 80cm telescope
  37. GRB 241229B: CrAO ZTSh possible optical counterpart of SVOM/VT confirmation
  38. Konus-Wind detection of GRB 241228A
  39. EP240702a: 7DT Optical upper limits
  40. GRB 240606B: 7DT Optical upper limits
  41. GRB 241228B: Swift-XRT afterglow detection
  42. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  43. Fermi GRB 241228B: Global MASTER-Net observations report
  44. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  45. GRB 241228A: Swift-XRT refined Analysis
  46. GRB 241228A: Swift detection of a burst
  47. GRB 241217A/EP241217b: continued SOAR observations
  48. Fermi GRB 241226A: Global MASTER-Net observations report
  49. Fermi trigger No 756678579: Global MASTER-Net observations report
  50. IceCube Alert 241224.30: Global MASTER-Net observations report
  51. EP241223a: Global MASTER-Net observations report
  52. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  53. GRB241113A: 7DT Optical upper limits
  54. Fermi Gamma-ray Burst Monitor trigger 756678579 / 241223854 is not a GRB
  55. Fermi GRB 241223A: Global MASTER-Net observations report
  56. GRB 241223A: GOTO optical observations summary
  57. EP241217a: e-MERLIN radio observations
  58. GRB 241217A / EP241217b: Non-detection in ATCA Radio Follow-up Observations
  59. Fermi trigger No 756447119: Global MASTER-Net observations report
  60. GRB 241217A/EP241217b: SOAR afterglow detection
  61. EP241217a: Liverpool Telescope optical upper limit
  62. GRB 241218A: Mondy AZT-33IK optical upper limit
  63. Konus-Wind detection of GRB 241204A (short/hard)
  64. EP 241217a: NIR detection with P200/WIRC
  65. GRB 241217A / EP241217b: NOT optical upper limits
  66. GRB 241218A: Swift-XRT refined Analysis
  67. EP241119a: 7DT Optical upper limits
  68. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  69. EP241217a: Global MASTER-Net observations report
  70. GRB 241218A: Swift detection of a burst
  71. EP241217a: Swift-XRT Detection
  72. EP241217a: EP detection of an X-ray transient
  73. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  74. Konus-Wind detection of GRB 241213A (EP 241213a)
  75. The EP-WXT trigger 01709128948 is likely a flaring star
  76. GRB 241215A: A long GRB detected by INTEGRAL
  77. GRB 241213A: Swift-XRT refined Analysis
  78. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  79. GRB 241213B: MAXI/GSC detection
  80. GRB 241213A: Swift detection of a burst
  81. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  82. Konus-Wind detection of GRB 241209B
  83. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  84. Konus-Wind detection of GRB 241209D
  85. GRB 241209C: Fermi GBM Observation
  86. GRB 241209A: Swift-XRT refined Analysis
  87. GRB 241209A: EP-FXT follow-up observations
  88. EP241208a: Global MASTER-Net observations report
  89. EP241208a: EP-FXT follow-up observations
  90. Fermi trigger No 755485387: Global MASTER-Net observations report
  91. GRB 241207B: Fermi GBM Observation
  92. GRB 241209D: Swift-XRT refined Analysis
  93. GRB 241209D: COLIBRÍ detection of the afterglow
  94. Fermi GRB 241209D: Global MASTER-Net observations report
  95. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  96. Swift GRB 241209D: Global MASTER-Net observations report
  97. Fermi GRB 241209A: Global MASTER-Net observations report
  98. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  99. EP241208a: EP detection of a fast X-ray transient
  100. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst

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