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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"

43132 results found.

  1. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  2. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  3. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  4. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  5. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  6. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  7. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  8. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  9. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  10. GRB 241120A: GRBAlpha detection
  11. GRB 241113B: SVOM/VT optical afterglow observations
  12. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  13. Konus-Wind detection of GRB 241117A
  14. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  15. GRB 241105A: ATCA radio detection
  16. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  17. IPN triangulation of GRB 241117A
  18. GRB 241026A: VIRT Optical Upper Limit
  19. GRB 241025A: VIRT Optical Upper Limit
  20. Konus-Wind detection of GRB 241120A
  21. GRB241120A: OHP/T193 optical observations
  22. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  23. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  24. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  25. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  26. GRB 241120A: Mondy and AbAO optical observations
  27. EP241119a: Optical upper limits with Kinder observations
  28. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  29. EP241119a: GIT optical upper limits
  30. GRB 241113A: Possible ATCA Radio detection
  31. EP241119a : J-band observations with WINTER
  32. GRB 241120A: Fermi GBM Observation
  33. GRB 241114B: Insight-HXMT/HE detection
  34. Integral GRB241120.25: Global MASTER-Net observations report
  35. EP241119a: Global MASTER-Net observations report
  36. EP241119a: EP detection of a fast X-ray transient
  37. GRB241120A: a long GRB detected by INTEGRAL
  38. GRB 241120A: Fermi GBM Final Real-time Localization
  39. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  40. GRB 241112B: Mephisto further optical observations
  41. GRB 241119A: Fermi GBM Final Real-time Localization
  42. GRB 241030A: J-band observations
  43. GRB 241115a: PRIME near-infrared upper limits
  44. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  45. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  46. GRB 241115B: Fermi GBM Observation
  47. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  48. Fermi GRB 241118A: Global MASTER-Net observations report
  49. GRB 241118A: Fermi GBM Final Real-time Localization
  50. Updates to IceCube realtime alert system for muon tracks
  51. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  52. GRB 241117A: Fermi GBM Detection
  53. Fermi GRB 241117B: Global MASTER-Net observations report
  54. GRB 241117B: Fermi GBM Final Real-time Localization
  55. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  56. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  57. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  58. Fermi GRB 241117A: Global MASTER-Net observations report
  59. GRB 241117A: Fermi GBM Final Real-time Localization
  60. GRB 241115C: Fermi GBM Observation
  61. GRB 241115A: Swift-XRT afterglow detection
  62. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  63. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  64. GRB 241115A: Mephisto upper limits
  65. GRB 241113B: Mephisto upper limits
  66. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  67. GRB 241115D / EP 241115a: SVOM/GRM observation
  68. The EP-WXT trigger 01709120856 is likely a flaring star
  69. EP241113a: Swift XRT weak detection
  70. GRB 241115A: Fermi GBM Observation
  71. GRB 241115A: LCOGT Optical Upper Limits
  72. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  73. Fermi GRB 241115B: Global MASTER-Net observations report
  74. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  75. EP241115a: Global MASTER-Net observations report
  76. GRB 241115B: Fermi GBM Final Real-time Localization
  77. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  78. EP241115a: EP detection of a fast X-ray transient
  79. EP241113a: No Detection in Fermi-GBM Observations
  80. Swift GRB 241115A: Global MASTER-Net observations report
  81. Fermi GRB 241115A: Global MASTER-Net observations report
  82. GRB 241115A: Swift detection of a burst
  83. GRB 241115A: Fermi GBM Final Real-time Localization
  84. EP 241113a: LBT possible optical counterpart
  85. GRB 241113B: KAIT Optical Afterglow Candidate
  86. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  87. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  88. GRB 241113A: Swift-BAT refined analysis
  89. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  90. GRB 241113A: PRIME near-infrared upper limits
  91. Fermi GRB 241114A: Global MASTER-Net observations report
  92. EP241113a: Global MASTER-Net observations report
  93. GRB 241114A: Fermi GBM Final Real-time Localization
  94. GRB 241113B: J-band upper limit from WINTER
  95. GRB 241113A: J-band observations with WINTER
  96. EP241113a : J-band observations with WINTER
  97. GRB 241030A: LCO optical observation
  98. GRB 241113B: Swift-XRT observations
  99. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  100. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits

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