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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"

32719 results found.

  1. LIGO/Virgo/KAGRA S241125n: Updated Coincidence with External Event
  2. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  3. LIGO/Virgo/KAGRA S241125n: Updated Sky localization and Coincidence with External Event
  4. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  5. GRB 241120A: GRBAlpha detection
  6. GRB 241113B: SVOM/VT optical afterglow observations
  7. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  8. Konus-Wind detection of GRB 241117A
  9. LIGO/Virgo/KAGRA S241122a: Updated Sky localization and Source Classification
  10. GRB 241105A: ATCA radio detection
  11. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  12. IPN triangulation of GRB 241117A
  13. GRB 241026A: VIRT Optical Upper Limit
  14. GRB 241025A: VIRT Optical Upper Limit
  15. Konus-Wind detection of GRB 241120A
  16. GRB241120A: OHP/T193 optical observations
  17. GRB 241120A: CALET Gamma-Ray Burst Monitor detection
  18. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  19. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  20. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  21. GRB 241120A: Mondy and AbAO optical observations
  22. EP241119a: Optical upper limits with Kinder observations
  23. EP241119a: GIT optical upper limits
  24. GRB 241113A: Possible ATCA Radio detection
  25. EP241119a : J-band observations with WINTER
  26. GRB 241120A: Fermi GBM Observation
  27. EP241119a: Global MASTER-Net observations report
  28. GRB241120A: a long GRB detected by INTEGRAL
  29. GRB 241115A: CALET Gamma-Ray Burst Monitor detection
  30. GRB 241112B: Mephisto further optical observations
  31. GRB 241030A: J-band observations
  32. GRB 241115a: PRIME near-infrared upper limits
  33. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  34. GRB 241115B: Fermi GBM Observation
  35. LIGO/Virgo/KAGRA S241114y: Updated Sky localization
  36. Fermi GRB 241118A: Global MASTER-Net observations report
  37. Updates to IceCube realtime alert system for muon tracks
  38. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  39. Fermi GRB 241117B: Global MASTER-Net observations report
  40. LIGO/Virgo/KAGRA S241116cq: Updated Sky localization
  41. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  42. Fermi GRB 241117A: Global MASTER-Net observations report
  43. GRB 241115C: Fermi GBM Observation
  44. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  45. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  46. GRB 241115A: Mephisto upper limits
  47. GRB 241113B: Mephisto upper limits
  48. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  49. GRB 241115D / EP 241115a: SVOM/GRM observation
  50. The EP-WXT trigger 01709120856 is likely a flaring star
  51. EP241113a: Swift XRT weak detection
  52. GRB 241115A: Fermi GBM Observation
  53. GRB 241115A: LCOGT Optical Upper Limits
  54. Fermi GRB 241115B: Global MASTER-Net observations report
  55. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  56. EP241115a: Global MASTER-Net observations report
  57. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  58. EP241113a: No Detection in Fermi-GBM Observations
  59. Swift GRB 241115A: Global MASTER-Net observations report
  60. Fermi GRB 241115A: Global MASTER-Net observations report
  61. EP 241113a: LBT possible optical counterpart
  62. GRB 241113B: KAIT Optical Afterglow Candidate
  63. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  64. GRB 241113A: Swift-BAT refined analysis
  65. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  66. GRB 241113A: PRIME near-infrared upper limits
  67. Fermi GRB 241114A: Global MASTER-Net observations report
  68. EP241113a: Global MASTER-Net observations report
  69. GRB 241113B: J-band upper limit from WINTER
  70. GRB 241113A: J-band observations with WINTER
  71. EP241113a : J-band observations with WINTER
  72. GRB 241030A: LCO optical observation
  73. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  74. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  75. GRB 241113A: KAIT optical observations
  76. EP241113b: Global MASTER-Net observations report
  77. EP241113b/GRB 241113B: EP detection of GRB 241113B
  78. Fermi-LAT gamma-ray observations of IceCube-241113A
  79. GRB 241113B: SVOM/GRM observation
  80. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  81. EP241107a: SOAR upper limits
  82. GRB 241113A: Swift/UVOT Detection
  83. GRB 241113A: REM detection of the optical/NIR afterglow
  84. Konus-Wind detection of GRB 241107A (short/hard)
  85. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  86. GRB 241113B: Swift ToO observations
  87. GRB 241113A: LCO optical observations
  88. GRB 241112B: GMG Optical Upper Limit
  89. GRB241113A: LCOGT (40-cm) optical counterpart detection
  90. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  91. SVOM/GRM detection of a short burst from SGR 1E1841-045
  92. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  93. GRB 241105A: ATCA Radio Upper Limits
  94. GRB 241112B: AbAO optical upper limit
  95. GRB 241107A: GROWTH-India telescope optical upper limit
  96. Fermi GRB 241112A: Global MASTER-Net observations report
  97. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  98. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  99. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  100. GRB 241112B: SVOM/GRM observation

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