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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"

43166 results found.

  1. GRB 240916B: Fermi GBM Final Real-time Localization
  2. GRB 240914B: Fermi GBM Final Localization
  3. The EP-WXT triggers 01709047257 and 01709047278 are not real sources
  4. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  5. EP EP240913a: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  7. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  8. GRB 240916A: Fermi GBM Final Real-time Localization
  9. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  10. EP240913a: VLT/HAWK-I near-infrared upper limits
  11. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  12. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  13. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  14. EP240913a/GRB 240913C: KAIT optical upper limit
  15. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  16. GRB 240913C: Fermi GBM detection
  17. GRB 240914A: Swift-XRT observations
  18. GRB 240913C: Joint location by ETJASMIN
  19. GRB 240914B: AstroSat CZTI detection
  20. EP240913A / GRB 240913C: AstroSat CZTI detection
  21. GRB 240914A: SVOM/GRM observation
  22. GRB 240910A: SVOM/VT optical observations
  23. GRB 240914A: Swift ToO observations
  24. EP240913a: NOT optical upper limits
  25. EP240913a: JinShan optical upper limits
  26. EP240913a: ESO-NTT optical observations
  27. GRB 240914A: ESO-NTT optical observations
  28. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  29. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  30. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  31. GRB 240905E: further NOT optical observations
  32. EP240913a: A GRB Event
  33. EP240913a: EP-WXT detection of a fast X-ray transient
  34. GRB 240913B: Fermi GBM Final Real-time Localization
  35. GRB 240911A: LCO optical observations
  36. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  37. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  38. GRB 240912A: Swift/UVOT Detection
  39. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  40. Fermi trigger No 747920561: Global MASTER-Net observations report
  41. GRB 240912A: SVOM/GRM observation
  42. GRB 240911A: Swift-XRT observations
  43. Fermi GRB 240913A: Global MASTER-Net observations report
  44. GRB 240913A: Fermi GBM Final Real-time Localization
  45. GRB 240912A: J-band observations with WINTER
  46. GRB 240912A: Swift-XRT refined Analysis
  47. GRB 240912A: Fermi GBM Observation
  48. Swift GRB 240912A: Global MASTER-Net observations report
  49. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  50. GRB 240911A: Tiled Swift observations
  51. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  52. GRB 240912B: Fermi GBM Final Real-time Localization
  53. GRB 240912A: NOT optical spectroscopy
  54. GRB 240912A: Enhanced Swift-XRT position
  55. GRB 240912A: Redshift from OSIRIS+/GTC
  56. Fast X-ray Transient EP240801a: GMRT radio observations
  57. GRB 240910A: Redshift from OSIRIS+/GTC
  58. GRB 240912A: Swift detection of a burst with an optical counterpart
  59. GRB 240912A: Fermi GBM Final Real-time Localization
  60. GRB 240910A: Fermi GBM Observation
  61. GRB 240910A: NOT optical observations
  62. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  63. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  64. GRB 240910A: JinShan optical observations
  65. GRB 240910A: GOTO candidate optical counterpart
  66. EP240908a: Optical afterglow confirmation
  67. GRB 240710A: SVOM/GRM observation
  68. GRB 240910A: Swift ToO observations
  69. IPN triangulation of GRB 240905B (short)
  70. GRB 240825A: 7DT Optical Upper Limit
  71. GRB 240905E: SVOM/VT optical observations
  72. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  73. GRB 240910A: GRBAlpha detection
  74. GRB 240910B: Fermi GBM Final Real-time Localization
  75. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  76. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  77. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  78. GRB 240910A: SVOM/GRM observation
  79. EP240908a: Mondy and AbAO follow-up observations
  80. EP240908a: Updates on the WXT detection result around the trigger time
  81. Fermi GRB 240910A: Global MASTER-Net observations report
  82. GRB 240910A: Fermi GBM Final Real-time Localization
  83. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  84. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  85. EP240908a: optical afterglow candidate
  86. EP EP240908a: Global MASTER-Net observations report
  87. GRB 240905B: Fermi GBM Observation
  88. Fermi trigger No 747553301: Global MASTER-Net observations report
  89. EP240908a: TRT optical upper limit
  90. GRB 240905B: GOTO optical upper limits
  91. EP240908a: EP detection of a fast X-ray transient
  92. Fermi GRB 240908A: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  94. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  95. GRB 240908A: Fermi GBM Final Real-time Localization
  96. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  99. GRB 240801A: SVOM/GRM observation
  100. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate

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