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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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"

32537 results found.

  1. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  2. EP240918a: Swift-XRT observation
  3. Fermi GRB 240918A: Global MASTER-Net observations report
  4. EP EP240918a: Global MASTER-Net observations report
  5. EP240918a: JinShan optical upper limits
  6. EP240918a: YAHPT Optical Upper Limit
  7. EP240918a: Optical upper limits with Kinder observations
  8. EP240918a: GMG Optical Upper Limit
  9. GRB 240916A: GRBAlpha detection
  10. GRB 240914B: GRBAlpha detection
  11. GRB 240916A: NOT optical observation
  12. GRB 240912A: Swift-BAT refined analysis
  13. IPN triangulation of GRB 240913C / EP 240913a
  14. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  15. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  16. GRB 240916A: Fermi GBM Observation
  17. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  18. GRB 240821A: radio observation with the VLA
  19. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  20. GRB 240916A: Swift-XRT afterglow detection
  21. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  22. GRB 240916A: Swift ToO observations
  23. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  24. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  25. EP EP240913a: Global MASTER-Net observations report
  26. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  27. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  28. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  29. EP240913a: VLT/HAWK-I near-infrared upper limits
  30. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  32. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  33. EP240913a/GRB 240913C: KAIT optical upper limit
  34. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  35. GRB 240913C: Fermi GBM detection
  36. GRB 240913C: Joint location by ETJASMIN
  37. GRB 240914B: AstroSat CZTI detection
  38. EP240913A / GRB 240913C: AstroSat CZTI detection
  39. GRB 240914A: SVOM/GRM observation
  40. GRB 240910A: SVOM/VT optical observations
  41. GRB 240914A: Swift ToO observations
  42. EP240913a: NOT optical upper limits
  43. EP240913a: JinShan optical upper limits
  44. EP240913a: ESO-NTT optical observations
  45. GRB 240914A: ESO-NTT optical observations
  46. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  47. GRB 240905E: further NOT optical observations
  48. EP240913a: A GRB Event
  49. GRB 240911A: LCO optical observations
  50. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  51. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  52. GRB 240912A: Swift/UVOT Detection
  53. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  54. GRB 240912A: SVOM/GRM observation
  55. Fermi GRB 240913A: Global MASTER-Net observations report
  56. GRB 240912A: J-band observations with WINTER
  57. GRB 240912A: Fermi GBM Observation
  58. Swift GRB 240912A: Global MASTER-Net observations report
  59. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  60. GRB 240911A: Tiled Swift observations
  61. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  62. GRB 240912A: NOT optical spectroscopy
  63. GRB 240912A: Redshift from OSIRIS+/GTC
  64. Fast X-ray Transient EP240801a: GMRT radio observations
  65. GRB 240910A: Redshift from OSIRIS+/GTC
  66. GRB 240910A: Fermi GBM Observation
  67. GRB 240910A: NOT optical observations
  68. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  69. GRB 240910A: JinShan optical observations
  70. GRB 240910A: GOTO candidate optical counterpart
  71. EP240908a: Optical afterglow confirmation
  72. GRB 240710A: SVOM/GRM observation
  73. GRB 240910A: Swift ToO observations
  74. IPN triangulation of GRB 240905B (short)
  75. GRB 240825A: 7DT Optical Upper Limit
  76. GRB 240905E: SVOM/VT optical observations
  77. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  78. GRB 240910A: GRBAlpha detection
  79. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  80. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  81. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  82. GRB 240910A: SVOM/GRM observation
  83. EP240908a: Mondy and AbAO follow-up observations
  84. EP240908a: Updates on the WXT detection result around the trigger time
  85. Fermi GRB 240910A: Global MASTER-Net observations report
  86. EP240908a: optical afterglow candidate
  87. EP EP240908a: Global MASTER-Net observations report
  88. GRB 240905B: Fermi GBM Observation
  89. EP240908a: TRT optical upper limit
  90. GRB 240905B: GOTO optical upper limits
  91. Fermi GRB 240908A: Global MASTER-Net observations report
  92. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  93. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  94. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  96. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  97. GRB 240801A: SVOM/GRM observation
  98. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  99. GRB 240905E: GIT optical upper limit
  100. GRB 240905E: Gaoyazi/GOT optical upper limits

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