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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"

24507 results found.

  1. LIGO/Virgo S241127aj: GRANDMA/FRAM-CTA-N Observations
  2. Fermi trigger No 754492985: Global MASTER-Net observations report
  3. GRB 241128A: Swift-XRT afterglow detection
  4. GRB 241128A: Swift detection of a burst
  5. LIGO/Virgo/KAGRA S241127aj: Updated Sky localization
  6. The EP-WXT trigger 01709125191 is not a real source
  7. Swift GRB241127.91: Global MASTER-Net OT detection
  8. EP241126a: WFST Observations
  9. IceCube Alert 241127.59: Global MASTER-Net observations report
  10. GRB 241127A: Swift detection of a burst with an optical counterpart
  11. Swift GRB241127.91: Global MASTER-Net observations report
  12. Swift GRB241127.91: Global MASTER-Net OT detection
  13. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  14. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  15. IceCube-241127A: IceCube observation of a high-energy neutrino candidate track-like event
  16. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  17. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  18. GRB 241126A: SVOM/GRM observation
  19. IPN triangulation of GRB 241114B
  20. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  21. EP241126a: EP-FXT follow-up observation update
  22. EP241126a: TRT optical counterpart detection
  23. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  24. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  25. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  26. GECAM detection of a short burst from SGR 1830
  27. Konus-Wind detection of GRB 241115D / EP 241115a
  28. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  29. EP241125a: Optical upper limit with Kinder observations
  30. EP241125a: EP detection of an X-ray transient
  31. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  32. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  33. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  34. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  35. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  36. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  37. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  38. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  39. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  40. GRB 241120A: GRBAlpha detection
  41. GRB 241113B: SVOM/VT optical afterglow observations
  42. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  43. Konus-Wind detection of GRB 241117A
  44. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  45. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  46. IPN triangulation of GRB 241117A
  47. Konus-Wind detection of GRB 241120A
  48. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  49. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  50. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  51. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  52. GRB 241120A: Mondy and AbAO optical observations
  53. EP241119a: Optical upper limits with Kinder observations
  54. GRB 241113A: Possible ATCA Radio detection
  55. EP241119a : J-band observations with WINTER
  56. GRB 241120A: Fermi GBM Observation
  57. Integral GRB241120.25: Global MASTER-Net observations report
  58. EP241119a: Global MASTER-Net observations report
  59. GRB241120A: a long GRB detected by INTEGRAL
  60. GRB 241120A: Fermi GBM Final Real-time Localization
  61. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  62. GRB 241112B: Mephisto further optical observations
  63. GRB 241119A: Fermi GBM Final Real-time Localization
  64. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  65. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  66. GRB 241115B: Fermi GBM Observation
  67. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  68. Fermi GRB 241118A: Global MASTER-Net observations report
  69. GRB 241118A: Fermi GBM Final Real-time Localization
  70. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  71. GRB 241117A: Fermi GBM Detection
  72. Fermi GRB 241117B: Global MASTER-Net observations report
  73. GRB 241117B: Fermi GBM Final Real-time Localization
  74. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  75. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  76. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  77. Fermi GRB 241117A: Global MASTER-Net observations report
  78. GRB 241117A: Fermi GBM Final Real-time Localization
  79. GRB 241115C: Fermi GBM Observation
  80. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  81. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  82. GRB 241115A: Mephisto upper limits
  83. GRB 241113B: Mephisto upper limits
  84. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  85. GRB 241115D / EP 241115a: SVOM/GRM observation
  86. GRB 241115A: Fermi GBM Observation
  87. GRB 241115A: LCOGT Optical Upper Limits
  88. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  89. Fermi GRB 241115B: Global MASTER-Net observations report
  90. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  91. EP241115a: Global MASTER-Net observations report
  92. GRB 241115B: Fermi GBM Final Real-time Localization
  93. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  94. EP241113a: No Detection in Fermi-GBM Observations
  95. Swift GRB 241115A: Global MASTER-Net observations report
  96. Fermi GRB 241115A: Global MASTER-Net observations report
  97. GRB 241115A: Fermi GBM Final Real-time Localization
  98. EP 241113a: LBT possible optical counterpart
  99. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  100. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations

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