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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"

21948 results found.

  1. IPN triangulation of GRB 240913C / EP 240913a
  2. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  3. GRB 240821A: radio observation with the VLA
  4. GRB 240916A: Swift-XRT afterglow detection
  5. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  6. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  7. EP240913a: VLT/HAWK-I near-infrared upper limits
  8. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  10. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  11. GRB 240914A: Swift-XRT observations
  12. GRB 240914B: AstroSat CZTI detection
  13. EP240913A / GRB 240913C: AstroSat CZTI detection
  14. GRB 240910A: SVOM/VT optical observations
  15. EP240913a: NOT optical upper limits
  16. EP240913a: JinShan optical upper limits
  17. EP240913a: ESO-NTT optical observations
  18. GRB 240914A: ESO-NTT optical observations
  19. GRB 240905E: further NOT optical observations
  20. EP240913a: A GRB Event
  21. EP240913a: EP-WXT detection of a fast X-ray transient
  22. GRB 240911A: LCO optical observations
  23. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  24. GRB 240912A: Swift/UVOT Detection
  25. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  26. GRB 240912A: J-band observations with WINTER
  27. GRB 240912A: Swift-XRT refined Analysis
  28. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  29. GRB 240912A: Enhanced Swift-XRT position
  30. GRB 240912A: Redshift from OSIRIS+/GTC
  31. Fast X-ray Transient EP240801a: GMRT radio observations
  32. GRB 240912A: Swift detection of a burst with an optical counterpart
  33. GRB 240910A: JinShan optical observations
  34. GRB 240910A: GOTO candidate optical counterpart
  35. IPN triangulation of GRB 240905B (short)
  36. GRB 240825A: 7DT Optical Upper Limit
  37. GRB 240905E: SVOM/VT optical observations
  38. GRB 240910A: GRBAlpha detection
  39. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  40. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  41. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  42. GRB 240910A: SVOM/GRM observation
  43. EP240908a: Mondy and AbAO follow-up observations
  44. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  45. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  46. EP240908a: TRT optical upper limit
  47. GRB 240905B: GOTO optical upper limits
  48. EP240908a: EP detection of a fast X-ray transient
  49. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  50. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  51. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  52. GRB 240905E: GIT optical upper limit
  53. GRB 240905B: Swift-XRT observations
  54. GRB 240905E: Gaoyazi/GOT optical upper limits
  55. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  56. GRB 240905E: J-band observations with WINTER
  57. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  58. GRB 240905E: AKO Optical Upper Limit
  59. GRB 240905E: SVOM/C-GFT optical upper limit
  60. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  61. Fermi GRB 240905D: Global MASTER-Net observations report
  62. GRB 240905E: NOT optical upper limits
  63. GRB 240905E: REM optical/NIR upper limits
  64. GRB 240905E: LCOGT Optical Upper Limit
  65. GRB 240905E: Swift/UVOT Upper Limits
  66. GRB 240905E: SAO RAS optical upper limit
  67. GRB 240905E: Nanshan/HMT optical upper limit
  68. GRB 240905E: Swift detection of a burst
  69. GRB 240819A: Optical upper limits from TESS
  70. GRB 240905D: Fermi GBM Final Real-time Localization
  71. GRB 240905C: Fermi GBM Final Real-time Localization
  72. GRB 240905B: Fermi GBM Final Real-time Localization
  73. GRB 240905A: Fermi GBM Final Real-time Localization
  74. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  75. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  76. LIGO/Virgo/KAGRA S240902bq: Identification of a GW compact binary merger candidate
  77. GRB 240825A: MeerLICHT afterglow detection
  78. GRB 240828A: SAO RAS AS-500(2) optical observations
  79. GRB 240825A: TSHAO Optical Upper Limit
  80. GRB 240829B: GRBAlpha detection
  81. GRB240828B: REM optical/NIR upper limits
  82. GRB 240828B: AbAO optical upper limit
  83. GRB 240825A: SOAR observations
  84. GRB 240828B: Mephisto optical upper limit
  85. GRB 240828B: GRANDMA Optical Upper Limit
  86. LIGO/Virgo/KAGRA S240830gn: Updated Sky localization and EM Bright Classification
  87. LIGO/Virgo/KAGRA S240830gn: Identification of a GW compact binary merger candidate
  88. GRB 240828B: J-band upper limit from WINTER
  89. GRB 240828B: GMG Optical Upper Limit
  90. GRB 240828B: SVOM/C-GFT optical upper limit
  91. GRB 240828B: SAO RAS optical upper limit
  92. GRB 240828A: SAO RAS optical observations
  93. GRB 240828A: KAIT Optical Afterglow Candidate
  94. GRB 240825A: SVOM/VT optical detection
  95. GRB 240825A: further SAO RAS optical observations
  96. GRB 240825A: iTelescope optical observations
  97. GRB 240828B: Swift-XRT afterglow detection
  98. GRB 240828A: AstroSat CZTI detection of a long burst
  99. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  100. GRB 240825A: Upper limits from a neutrino search with IceCube

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