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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"

32689 results found.

  1. LIGO/Virgo/KAGRA S240925n: Updated Sky localization and Source Classification
  2. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  3. GRB 240716A: Swift/BAT-GUANO localization skymap of a long burst
  4. LIGO/Virgo/KAGRA S240925n: Identification of a GW compact binary merger candidate
  5. Konus-Wind detection of GRB 240918B
  6. IPN triangulation of GRB 240918B
  7. GRB 240905B: VZLUSAT-2 detection
  8. LIGO/Virgo/KAGRA S240922df: Updated Sky localization
  9. LIGO/Virgo/KAGRA S240920dw: Updated Sky localization
  10. LIGO/Virgo/KAGRA S240921cw: Updated Sky localization
  11. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  12. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  13. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  14. EP trigger ID 01709059262: correction to the observation start time and source localization
  15. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  16. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo S240919bn: GOTO optical upper limits
  18. GRB 240918B: AstroSat CZTI detection
  19. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  21. EP240919a: EP-FXT follow-up observation update
  22. EP240913A/GRB 240913C: AbAO optical upper limit
  23. EP240919a / GRB 240919A: Mondy optical upper limit
  24. EP240913a/GRB 240913C: 1.6m Mephisto observations
  25. EP240918a: SVOM/VT upper limit
  26. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  27. EP240919a / GRB 240919A: REM optical and NIR upper limits
  28. EP240919a / GRB 240919A: KAIT optical upper limit
  29. EP240918b and EP240918c: Optical upper limits with Kinder observations
  30. GRB 240414A: further radio observations with the VLA
  31. EP240919a: Optical upper limit with Kinder observations
  32. GRB 240919A / EP240919a: SVOM/GRM observation
  33. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  34. EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
  35. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  36. EP EP240919a: Global MASTER-Net observations report
  37. GRB 240910A: radio detection with the VLA
  38. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  39. EP240919a: NOT and Gemini optical observations
  40. EP240919a: GOTO optical upper limits
  41. EP240919a: JinShan optical upper limits
  42. EP240919a is likely a GRB event (duplicate submission of 37563)
  43. EP240919a is likely a GRB event
  44. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  45. GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE
  46. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  47. GRB 240918B: Fermi GBM Detection
  48. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  49. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  50. EP240918a: EP observation update
  51. GRB 240910A: further Swift observations and confirmation of afterglow
  52. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  53. EP240918a: Swift-XRT observation
  54. Fermi GRB 240918A: Global MASTER-Net observations report
  55. EP EP240918a: Global MASTER-Net observations report
  56. EP240918a: JinShan optical upper limits
  57. EP240918a: YAHPT Optical Upper Limit
  58. EP240918a: Optical upper limits with Kinder observations
  59. EP240918a: GMG Optical Upper Limit
  60. GRB 240916A: GRBAlpha detection
  61. GRB 240914B: GRBAlpha detection
  62. GRB 240916A: NOT optical observation
  63. GRB 240912A: Swift-BAT refined analysis
  64. IPN triangulation of GRB 240913C / EP 240913a
  65. GRB 240825A: INTEGRAL SPI ACS LIGHT CURVE
  66. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  67. GRB 240916A: Fermi GBM Observation
  68. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  69. GRB 240821A: radio observation with the VLA
  70. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  71. GRB 240916A: Swift-XRT afterglow detection
  72. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  73. GRB 240916A: Swift ToO observations
  74. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  75. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  76. EP EP240913a: Global MASTER-Net observations report
  77. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  78. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  79. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  80. EP240913a: VLT/HAWK-I near-infrared upper limits
  81. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  83. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  84. EP240913a/GRB 240913C: KAIT optical upper limit
  85. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  86. GRB 240913C: Fermi GBM detection
  87. GRB 240913C: Joint location by ETJASMIN
  88. GRB 240914B: AstroSat CZTI detection
  89. EP240913A / GRB 240913C: AstroSat CZTI detection
  90. GRB 240914A: SVOM/GRM observation
  91. GRB 240910A: SVOM/VT optical observations
  92. GRB 240914A: Swift ToO observations
  93. EP240913a: NOT optical upper limits
  94. EP240913a: JinShan optical upper limits
  95. EP240913a: ESO-NTT optical observations
  96. GRB 240914A: ESO-NTT optical observations
  97. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  98. GRB 240905E: further NOT optical observations
  99. EP240913a: A GRB Event
  100. GRB 240911A: LCO optical observations

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