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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"

24508 results found.

  1. EP240918a: YAHPT Optical Upper Limit
  2. GRB 240916A: GRBAlpha detection
  3. GRB 240914B: GRBAlpha detection
  4. GRB 240912A: Swift-BAT refined analysis
  5. IPN triangulation of GRB 240913C / EP 240913a
  6. GRB 240916A: Fermi GBM Observation
  7. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  8. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  10. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  11. GRB 240916B: Fermi GBM Final Real-time Localization
  12. GRB 240914B: Fermi GBM Final Localization
  13. The EP-WXT triggers 01709047257 and 01709047278 are not real sources
  14. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  15. EP EP240913a: Global MASTER-Net observations report
  16. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  17. GRB 240916A: Fermi GBM Final Real-time Localization
  18. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  19. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  21. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  22. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  23. GRB 240913C: Fermi GBM detection
  24. EP240913A / GRB 240913C: AstroSat CZTI detection
  25. GRB 240914A: SVOM/GRM observation
  26. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  27. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  28. GRB 240905E: further NOT optical observations
  29. EP240913a: A GRB Event
  30. GRB 240913B: Fermi GBM Final Real-time Localization
  31. Fermi trigger No 747920561: Global MASTER-Net observations report
  32. GRB 240911A: Swift-XRT observations
  33. Fermi GRB 240913A: Global MASTER-Net observations report
  34. GRB 240913A: Fermi GBM Final Real-time Localization
  35. GRB 240912A: Swift-XRT refined Analysis
  36. GRB 240912A: Fermi GBM Observation
  37. Swift GRB 240912A: Global MASTER-Net observations report
  38. GRB 240912B: Fermi GBM Final Real-time Localization
  39. GRB 240912A: NOT optical spectroscopy
  40. GRB 240912A: Fermi GBM Final Real-time Localization
  41. GRB 240910A: Fermi GBM Observation
  42. GRB 240910A: NOT optical observations
  43. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  44. GRB 240910A: JinShan optical observations
  45. GRB 240910A: GOTO candidate optical counterpart
  46. EP240908a: Optical afterglow confirmation
  47. IPN triangulation of GRB 240905B (short)
  48. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  49. GRB 240910A: GRBAlpha detection
  50. GRB 240910B: Fermi GBM Final Real-time Localization
  51. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  52. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  53. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  54. GRB 240910A: SVOM/GRM observation
  55. EP240908a: Updates on the WXT detection result around the trigger time
  56. Fermi GRB 240910A: Global MASTER-Net observations report
  57. GRB 240910A: Fermi GBM Final Real-time Localization
  58. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  59. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  60. EP240908a: optical afterglow candidate
  61. EP EP240908a: Global MASTER-Net observations report
  62. GRB 240905B: Fermi GBM Observation
  63. Fermi trigger No 747553301: Global MASTER-Net observations report
  64. GRB 240905B: GOTO optical upper limits
  65. EP240908a: EP detection of a fast X-ray transient
  66. Fermi GRB 240908A: Global MASTER-Net observations report
  67. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  68. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  69. GRB 240908A: Fermi GBM Final Real-time Localization
  70. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  72. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  74. GRB 240905B: Swift-XRT observations
  75. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  76. GRB 240905B: Fermi-LAT detection
  77. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  78. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  79. Fermi GRB 240905D: Global MASTER-Net observations report
  80. Fermi GRB 240905A: Global MASTER-Net observations report
  81. GRB 240905E: NOT optical upper limits
  82. GRB 240905E: REM optical/NIR upper limits
  83. GRB 240905E: SVOM/GRM observation
  84. GRB 240905E: LCOGT Optical Upper Limit
  85. GRB 240825A: Montarrenti Observatory optical follow-up observations
  86. Swift GRB 240905E: Global MASTER-Net observations report
  87. GRB 240905E: Swift detection of a burst
  88. GRB 240819A: Optical upper limits from TESS
  89. GRB 240905D: AstroSat CZTI detection
  90. GRB 240905A: SVOM/GRM observation
  91. Fermi GRB 240905B: Global MASTER-Net observations report
  92. GRB 240905D: Fermi GBM Final Real-time Localization
  93. GRB 240905B: AstroSat CZTI detection and localization
  94. GRB 240905C: Fermi GBM Final Real-time Localization
  95. GRB 240905B: Fermi GBM Final Real-time Localization
  96. Swift GRB 240904A: Global MASTER-Net observations report
  97. GRB 240905A: Fermi GBM Final Real-time Localization
  98. Fermi trigger No 747163821: Global MASTER-Net observations report
  99. GRB 240904A: Swift detection of a burst
  100. GRB 240828A: SVOM/GRM observation

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