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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"

45822 results found.

  1. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  2. GRB 241126A: SVOM/GRM observation
  3. IPN triangulation of GRB 241114B
  4. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  5. EP241126a: EP-FXT follow-up observation update
  6. EP241126a: GSP detects optical counterpart
  7. EP241126a: TRT optical counterpart detection
  8. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  9. EP241126a: EP detection of a fast X-ray transient
  10. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  11. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  12. LIGO/Virgo/KAGRA S241126dm: Retraction of GW compact binary merger candidate
  13. Trigger_18947: Swift ToO observations (retracted)
  14. GRB 241113B: EP-FXT afterglow detection
  15. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  16. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  17. SVOM/GRM detection of a short burst from SGR 1830
  18. GECAM detection of a short burst from SGR 1830
  19. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  20. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  21. Konus-Wind detection of GRB 241115D / EP 241115a
  22. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  23. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  24. GRB 241026A: radio detection with the VLA
  25. EP241125a: Optical upper limit with Kinder observations
  26. EP241125a: EP detection of an X-ray transient
  27. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  28. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  29. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  30. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  31. LIGO/Virgo/KAGRA S241125n: Updated Sky localization
  32. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  33. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  34. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  35. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  36. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  37. GRB 241120A: GRBAlpha detection
  38. GRB 241113B: SVOM/VT optical afterglow observations
  39. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  40. Konus-Wind detection of GRB 241117A
  41. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  42. GRB 241105A: ATCA radio detection
  43. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  44. IPN triangulation of GRB 241117A
  45. GRB 241026A: VIRT Optical Upper Limit
  46. GRB 241025A: VIRT Optical Upper Limit
  47. Konus-Wind detection of GRB 241120A
  48. GRB241120A: OHP/T193 optical observations
  49. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  50. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  51. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  52. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  53. GRB 241120A: Mondy and AbAO optical observations
  54. EP241119a: Optical upper limits with Kinder observations
  55. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  56. EP241119a: GIT optical upper limits
  57. GRB 241113A: Possible ATCA Radio detection
  58. EP241119a : J-band observations with WINTER
  59. GRB 241120A: Fermi GBM Observation
  60. GRB 241114B: Insight-HXMT/HE detection
  61. Integral GRB241120.25: Global MASTER-Net observations report
  62. EP241119a: Global MASTER-Net observations report
  63. EP241119a: EP detection of a fast X-ray transient
  64. GRB241120A: a long GRB detected by INTEGRAL
  65. GRB 241120A: Fermi GBM Final Real-time Localization
  66. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  67. GRB 241112B: Mephisto further optical observations
  68. GRB 241119A: Fermi GBM Final Real-time Localization
  69. GRB 241030A: J-band observations
  70. GRB 241115a: PRIME near-infrared upper limits
  71. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  72. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  73. GRB 241115B: Fermi GBM Observation
  74. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  75. Fermi GRB 241118A: Global MASTER-Net observations report
  76. GRB 241118A: Fermi GBM Final Real-time Localization
  77. Updates to IceCube realtime alert system for muon tracks
  78. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  79. GRB 241117A: Fermi GBM Detection
  80. Fermi GRB 241117B: Global MASTER-Net observations report
  81. GRB 241117B: Fermi GBM Final Real-time Localization
  82. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  83. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  84. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  85. Fermi GRB 241117A: Global MASTER-Net observations report
  86. GRB 241117A: Fermi GBM Final Real-time Localization
  87. GRB 241115C: Fermi GBM Observation
  88. GRB 241115A: Swift-XRT afterglow detection
  89. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  90. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  91. GRB 241115A: Mephisto upper limits
  92. GRB 241113B: Mephisto upper limits
  93. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  94. GRB 241115D / EP 241115a: SVOM/GRM observation
  95. The EP-WXT trigger 01709120856 is likely a flaring star
  96. EP241113a: Swift XRT weak detection
  97. GRB 241115A: Fermi GBM Observation
  98. GRB 241115A: LCOGT Optical Upper Limits
  99. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  100. Fermi GRB 241115B: Global MASTER-Net observations report

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