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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"

12124 results found.

  1. GRB 241217A/EP241217b: continued SOAR observations
  2. Fermi GRB 241226A: Global MASTER-Net observations report
  3. Fermi trigger No 756678579: Global MASTER-Net observations report
  4. IceCube Alert 241224.30: Global MASTER-Net observations report
  5. EP241223a: Global MASTER-Net observations report
  6. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  7. GRB241113A: 7DT Optical upper limits
  8. Fermi Gamma-ray Burst Monitor trigger 756678579 / 241223854 is not a GRB
  9. Fermi GRB 241223A: Global MASTER-Net observations report
  10. GRB 241223A: GOTO optical observations summary
  11. EP241217a: e-MERLIN radio observations
  12. GRB 241217A / EP241217b: Non-detection in ATCA Radio Follow-up Observations
  13. Fermi trigger No 756447119: Global MASTER-Net observations report
  14. GRB 241217A/EP241217b: SOAR afterglow detection
  15. EP241217a: Liverpool Telescope optical upper limit
  16. GRB 241218A: Mondy AZT-33IK optical upper limit
  17. Konus-Wind detection of GRB 241204A (short/hard)
  18. EP 241217a: NIR detection with P200/WIRC
  19. GRB 241217A / EP241217b: NOT optical upper limits
  20. GRB 241218A: Swift-XRT refined Analysis
  21. EP241119a: 7DT Optical upper limits
  22. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  23. EP241217a: Global MASTER-Net observations report
  24. GRB 241218A: Swift detection of a burst
  25. EP241217a: Swift-XRT Detection
  26. EP241217a: EP detection of an X-ray transient
  27. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  28. Konus-Wind detection of GRB 241213A (EP 241213a)
  29. The EP-WXT trigger 01709128948 is likely a flaring star
  30. GRB 241215A: A long GRB detected by INTEGRAL
  31. GRB 241213A: Swift-XRT refined Analysis
  32. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  33. GRB 241213B: MAXI/GSC detection
  34. GRB 241213A: Swift detection of a burst
  35. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  36. Konus-Wind detection of GRB 241209B
  37. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  38. Konus-Wind detection of GRB 241209D
  39. GRB 241209C: Fermi GBM Observation
  40. GRB 241209A: Swift-XRT refined Analysis
  41. GRB 241209A: EP-FXT follow-up observations
  42. EP241208a: Global MASTER-Net observations report
  43. EP241208a: EP-FXT follow-up observations
  44. Fermi trigger No 755485387: Global MASTER-Net observations report
  45. GRB 241207B: Fermi GBM Observation
  46. GRB 241209D: Swift-XRT refined Analysis
  47. GRB 241209D: COLIBRÍ detection of the afterglow
  48. Fermi GRB 241209D: Global MASTER-Net observations report
  49. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  50. Swift GRB 241209D: Global MASTER-Net observations report
  51. Fermi GRB 241209A: Global MASTER-Net observations report
  52. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  53. EP241208a: EP detection of a fast X-ray transient
  54. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  55. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  56. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  57. GRB 241207C: MAXI/GSC detection
  58. GRB 241207B: Fermi GBM Final Real-time Localization
  59. Fermi GRB 241207A: Global MASTER-Net observations report
  60. EP241206a: Global MASTER-Net observations report
  61. EP241206a: EP detection of a fast X-ray transient
  62. GRB 241206A: Fermi GBM observation
  63. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  64. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  65. Fermi GRB 241206A: Global MASTER-Net observations report
  66. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  67. GRB 241204A: Fermi-LAT detection
  68. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  69. Konus-Wind detection of GRB 241130A
  70. EP241201a: BOOTES-5 optical upper limit
  71. EP241202b: EP detection of a fast X-ray transient
  72. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  73. EP241201a: Global MASTER-Net observations report
  74. GRB 241127B: detection of a long GRB by SVOM/ECLAIRs
  75. Fermi trigger No 754701230: Global MASTER-Net observations report
  76. Konus-Wind detection of GRB 241114B
  77. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  78. Fermi-LAT gamma-ray observations of IceCube-241127A
  79. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  80. GRB 241128A: Swift-XRT refined Analysis
  81. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  82. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  83. GRB 241127A: Swift-XRT refined Analysis
  84. GRB 241127A: Swift detection of a burst with an optical counterpart
  85. Swift GRB241127.91: Global MASTER-Net observations report
  86. Swift GRB241127.91: Global MASTER-Net OT detection
  87. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  88. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  89. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  90. EP241126a: EP-FXT follow-up observation update
  91. EP241126a: EP detection of a fast X-ray transient
  92. SVOM/GRM detection of a short burst from SGR 1830
  93. GECAM detection of a short burst from SGR 1830
  94. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  95. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  96. Konus-Wind detection of GRB 241115D / EP 241115a
  97. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  98. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  99. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  100. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart

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