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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"

45822 results found.

  1. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  2. EP241115a: Global MASTER-Net observations report
  3. GRB 241115B: Fermi GBM Final Real-time Localization
  4. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  5. EP241115a: EP detection of a fast X-ray transient
  6. EP241113a: No Detection in Fermi-GBM Observations
  7. Swift GRB 241115A: Global MASTER-Net observations report
  8. Fermi GRB 241115A: Global MASTER-Net observations report
  9. GRB 241115A: Swift detection of a burst
  10. GRB 241115A: Fermi GBM Final Real-time Localization
  11. EP 241113a: LBT possible optical counterpart
  12. GRB 241113B: KAIT Optical Afterglow Candidate
  13. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  14. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  15. GRB 241113A: Swift-BAT refined analysis
  16. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  17. GRB 241113A: PRIME near-infrared upper limits
  18. Fermi GRB 241114A: Global MASTER-Net observations report
  19. EP241113a: Global MASTER-Net observations report
  20. GRB 241114A: Fermi GBM Final Real-time Localization
  21. GRB 241113B: J-band upper limit from WINTER
  22. GRB 241113A: J-band observations with WINTER
  23. EP241113a : J-band observations with WINTER
  24. GRB 241030A: LCO optical observation
  25. GRB 241113B: Swift-XRT observations
  26. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  27. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  28. GRB 241113A: KAIT optical observations
  29. EP241113b: Global MASTER-Net observations report
  30. EP241113b/GRB 241113B: EP detection of GRB 241113B
  31. Fermi-LAT gamma-ray observations of IceCube-241113A
  32. GRB 241113B: SVOM/GRM observation
  33. EP241113a: EP on-board trigger and autonomous follow-up observation
  34. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  35. GRB 241113A: Swift-XRT refined Analysis
  36. EP241107a: SOAR upper limits
  37. GRB 241113A: Swift/UVOT Detection
  38. GRB 241113A: REM detection of the optical/NIR afterglow
  39. Konus-Wind detection of GRB 241107A (short/hard)
  40. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  41. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  42. GRB 241113B: Swift ToO observations
  43. GRB 241113A: LCO optical observations
  44. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  45. GRB 241112B: GMG Optical Upper Limit
  46. GRB 241113A: Enhanced Swift-XRT position
  47. GRB241113A: LCOGT (40-cm) optical counterpart detection
  48. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  49. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  50. GRB 241113A: Swift detection of a burst with an optical counterpart
  51. Swift GRB241113.33: Global MASTER-Net observations report
  52. SVOM/GRM detection of a short burst from SGR 1E1841-045
  53. Fermi trigger No 753166198: Global MASTER-Net observations report
  54. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  55. GRB 241105A: ATCA Radio Upper Limits
  56. GRB 241112B: AbAO optical upper limit
  57. GRB 241107A: GROWTH-India telescope optical upper limit
  58. IceCube Alert 241113.02: Global MASTER-Net observations report
  59. Fermi GRB 241112A: Global MASTER-Net observations report
  60. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  61. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  62. GRB 241112B: Swift-XRT afterglow detection
  63. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  64. GRB 241112B: SVOM/GRM observation
  65. GRB 241112B: SVOM/VT afterglow detection
  66. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  67. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  68. GRB 241112B: Mephisto optical upper limits
  69. GRB 241112B: GOTO optical upper limits
  70. GRB 241112B: Swift ToO observations
  71. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  72. GRB 241107A: INTEGRAL IBIS localization
  73. EP241107a: EP-FXT follow-up observations
  74. GRB 241112A: Fermi GBM Final Real-time Localization
  75. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  76. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  77. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  78. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  79. IPN triangulation of GRB 241107A (short/hard)
  80. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  81. GRB 241025C: VZLUSAT-2 detection
  82. GRB 241025A: VZLUSAT-2 detection
  83. GRB 241018A: cubesat Avion detection
  84. Fermi trigger No 752990530: Global MASTER-Net observations report
  85. GRB 241111A: Fermi GBM Final Real-time Localization
  86. GRB 241030B: TESS detection of optical counterpart
  87. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  88. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  89. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  90. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  91. Fermi trigger No 752878030: Global MASTER-Net observations report
  92. Integral GRB241109.89: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  94. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  95. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  96. INTEGRAL detection of a burst from 1E 1841-045
  97. EP241107a: AbAO optical upper limit
  98. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  99. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  100. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification

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