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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"

43199 results found.

  1. GRB 240910A: Swift ToO observations
  2. IPN triangulation of GRB 240905B (short)
  3. GRB 240825A: 7DT Optical Upper Limit
  4. GRB 240905E: SVOM/VT optical observations
  5. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  6. GRB 240910A: GRBAlpha detection
  7. GRB 240910B: Fermi GBM Final Real-time Localization
  8. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  9. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  10. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  11. GRB 240910A: SVOM/GRM observation
  12. EP240908a: Mondy and AbAO follow-up observations
  13. EP240908a: Updates on the WXT detection result around the trigger time
  14. Fermi GRB 240910A: Global MASTER-Net observations report
  15. GRB 240910A: Fermi GBM Final Real-time Localization
  16. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  18. EP240908a: optical afterglow candidate
  19. EP EP240908a: Global MASTER-Net observations report
  20. GRB 240905B: Fermi GBM Observation
  21. Fermi trigger No 747553301: Global MASTER-Net observations report
  22. EP240908a: TRT optical upper limit
  23. GRB 240905B: GOTO optical upper limits
  24. EP240908a: EP detection of a fast X-ray transient
  25. Fermi GRB 240908A: Global MASTER-Net observations report
  26. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  27. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  28. GRB 240908A: Fermi GBM Final Real-time Localization
  29. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  32. GRB 240801A: SVOM/GRM observation
  33. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  34. GRB 240905E: GIT optical upper limit
  35. GRB 240905B: Swift-XRT observations
  36. GRB 240905E: Gaoyazi/GOT optical upper limits
  37. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  38. GRB 240905B: Fermi-LAT detection
  39. GRB 240905B: Swift ToO observations
  40. GRB 240905E: J-band observations with WINTER
  41. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  42. GRB 240905E: AKO Optical Upper Limit
  43. GRB 240905E: SVOM/C-GFT optical upper limit
  44. Fermi GRB 240905D: Global MASTER-Net observations report
  45. Fermi GRB 240905A: Global MASTER-Net observations report
  46. GRB 240905E: NOT optical upper limits
  47. GRB 240905E: REM optical/NIR upper limits
  48. GRB 240902B: AstroSat CZTI detection of a long burst
  49. GRB 240905E: Swift-XRT refined Analysis
  50. GRB 240902A: AstroSat CZTI detection of a long burst
  51. GRB 240905E: SVOM/GRM observation
  52. GRB 240905E: LCOGT Optical Upper Limit
  53. GRB 240905E: Swift/UVOT Upper Limits
  54. GRB 240905E: SAO RAS optical upper limit
  55. GRB 240825A: Montarrenti Observatory optical follow-up observations
  56. GRB 240905E: Nanshan/HMT optical upper limit
  57. Swift GRB 240905E: Global MASTER-Net observations report
  58. GRB 240905E: Swift detection of a burst
  59. GRB 240819A: Optical upper limits from TESS
  60. GRB 240905D: AstroSat CZTI detection
  61. GRB 240905A: SVOM/GRM observation
  62. Fermi GRB 240905B: Global MASTER-Net observations report
  63. GRB 240905D: Fermi GBM Final Real-time Localization
  64. GRB 240905B: AstroSat CZTI detection and localization
  65. GRB 240905C: Fermi GBM Final Real-time Localization
  66. GRB 240905B: Fermi GBM Final Real-time Localization
  67. GRB 240825A: ATCA Detection of Radio Counterpart
  68. Swift GRB 240904A: Global MASTER-Net observations report
  69. GRB 240905A: Fermi GBM Final Real-time Localization
  70. Fermi trigger No 747163821: Global MASTER-Net observations report
  71. GRB 240904A: Swift detection of a burst
  72. GRB 240828A: SVOM/GRM observation
  73. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  74. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  75. LIGO/Virgo/KAGRA S240902bq: Updated Sky localization
  76. GRB 240828A: GECAM detection
  77. GRB 240831B: Fermi GBM Final Localization
  78. LIGO/Virgo/KAGRA S240902bq: Identification of a GW compact binary merger candidate
  79. GRB 240825A: MeerLICHT afterglow detection
  80. Fermi trigger No 746923430: Global MASTER-Net observations report
  81. GRB 240828A: SAO RAS AS-500(2) optical observations
  82. GRB 240821A: VLT spectroscopic observations
  83. Fermi trigger No 746882332: Global MASTER-Net observations report
  84. GRB 240825A: TSHAO Optical Upper Limit
  85. GRB 240829B: GRBAlpha detection
  86. GRB240828B: REM optical/NIR upper limits
  87. Fermi trigger No 746816563: Global MASTER-Net observations report
  88. GRB 240831A: Fermi GBM Final Real-time Localization
  89. GRB 240825A: SOAR observations
  90. GRB 240828B: Mephisto optical upper limit
  91. GRB 240828B: GRANDMA Optical Upper Limit
  92. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  93. LIGO/Virgo/KAGRA S240830gn: Updated Sky localization and EM Bright Classification
  94. GRB 240825A: Swift-BAT refined analysis
  95. LIGO/Virgo/KAGRA S240830gn: Identification of a GW compact binary merger candidate
  96. GRB 240825A: MeerKAT detection
  97. GRB 240828B: J-band upper limit from WINTER
  98. Fermi trigger No 746684112: Global MASTER-Net observations report
  99. GRB 240828B: GMG Optical Upper Limit
  100. GRB 240828A: KAIT continued optical observations

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