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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').
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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"

28275 results found.

  1. LIGO/Virgo/KAGRA S240924a: Updated Sky localization
  2. LIGO/Virgo/KAGRA S240920bz: Updated Sky localization and Source Classification
  3. LIGO/Virgo/KAGRA S240923ct: Updated Sky localization and Source Classification
  4. LIGO/Virgo/KAGRA S240924a: Identification of a GW compact binary merger candidate
  5. LIGO/Virgo/KAGRA S240923ct: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo S240919bn: Swift XRT observations, 10 X-ray sources
  7. GRB 240918B: AstroSat CZTI detection
  8. LIGO/Virgo/KAGRA S240922df: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo/KAGRA S240921cw: Identification of a GW compact binary merger candidate
  10. EP240913A/GRB 240913C: AbAO optical upper limit
  11. EP240919a / GRB 240919A: Mondy optical upper limit
  12. EP240913a/GRB 240913C: 1.6m Mephisto observations
  13. EP240918a: SVOM/VT upper limit
  14. Fermi GBM Sub-Threshold Detection of GRB240919A / EP240919a
  15. EP240919a / GRB 240919A: REM optical and NIR upper limits
  16. EP240918b and EP240918c: Optical upper limits with Kinder observations
  17. GRB 240414A: further radio observations with the VLA
  18. EP240919a: Optical upper limit with Kinder observations
  19. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  20. GRB 240910A: radio detection with the VLA
  21. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  22. EP240919a: NOT and Gemini optical observations
  23. EP240919a: GOTO optical upper limits
  24. EP240919a: JinShan optical upper limits
  25. LIGO/Virgo/KAGRA S240920bz: Identification of a GW compact binary merger candidate
  26. LIGO/Virgo/KAGRA S240919bn: Updated Sky localization
  27. GRB 240918B: Fermi GBM Detection
  28. LIGO/Virgo/KAGRA S240917cb: Updated Sky localization and EM Bright Classification
  29. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  30. EP240918b and EP240918c: EP-WXT detection of two fast X-ray transients
  31. GRB 240910A: further Swift observations and confirmation of afterglow
  32. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  33. EP240918a: Swift-XRT observation
  34. EP240918a: JinShan optical upper limits
  35. EP240918a: Optical upper limits with Kinder observations
  36. EP240918a: GMG Optical Upper Limit
  37. EP240918a: an X-ray transient detected by Einstein Probe
  38. GRB 240912A: Swift-BAT refined analysis
  39. IPN triangulation of GRB 240913C / EP 240913a
  40. GRB 240916A: Fermi GBM Observation
  41. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  42. GRB 240821A: radio observation with the VLA
  43. GRB 240916A: Swift-XRT afterglow detection
  44. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  45. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  46. LIGO/Virgo S240915b: Swift XRT observations, 8 X-ray sources
  47. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  48. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  49. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  50. EP240913a: VLT/HAWK-I near-infrared upper limits
  51. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  52. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  53. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  54. GRB 240913C: Fermi GBM detection
  55. GRB 240914A: Swift-XRT observations
  56. GRB 240910A: SVOM/VT optical observations
  57. EP240913a: NOT optical upper limits
  58. EP240913a: JinShan optical upper limits
  59. EP240913a: ESO-NTT optical observations
  60. GRB 240914A: ESO-NTT optical observations
  61. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  62. GRB 240905E: further NOT optical observations
  63. EP240913a: EP-WXT detection of a fast X-ray transient
  64. GRB 240911A: LCO optical observations
  65. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  66. GRB 240912A: Swift/UVOT Detection
  67. GRB 240911A: Swift-XRT observations
  68. GRB 240912A: J-band observations with WINTER
  69. GRB 240912A: Swift-XRT refined Analysis
  70. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  71. GRB 240912A: Enhanced Swift-XRT position
  72. GRB 240912A: Redshift from OSIRIS+/GTC
  73. Fast X-ray Transient EP240801a: GMRT radio observations
  74. GRB 240912A: Swift detection of a burst with an optical counterpart
  75. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  76. GRB 240910A: JinShan optical observations
  77. IPN triangulation of GRB 240905B (short)
  78. GRB 240825A: 7DT Optical Upper Limit
  79. GRB 240905E: SVOM/VT optical observations
  80. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  81. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  82. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  83. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  84. GRB 240910A: SVOM/GRM observation
  85. EP240908a: Mondy and AbAO follow-up observations
  86. EP240908a: Updates on the WXT detection result around the trigger time
  87. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  88. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  89. GRB 240905B: Fermi GBM Observation
  90. Fermi trigger No 747553301: Global MASTER-Net observations report
  91. EP240908a: TRT optical upper limit
  92. EP240908a: EP detection of a fast X-ray transient
  93. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  94. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  95. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  96. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  98. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  99. GRB 240905E: GIT optical upper limit
  100. GRB 240905B: Swift-XRT observations

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