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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37335 results found.

  1. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  2. GRB 240821A: radio observation with the VLA
  3. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  4. GRB 240916A: Swift-XRT afterglow detection
  5. GRB 240916A: Swift ToO observations
  6. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  7. GRB 240916B: Fermi GBM Final Real-time Localization
  8. GRB 240914B: Fermi GBM Final Localization
  9. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  10. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  11. GRB 240916A INTEGRAL SPI ACS LIGHT CURVE
  12. GRB 240916A: Fermi GBM Final Real-time Localization
  13. Fermi Gamma-ray Burst Monitor trigger 748124309/240915846 is not a GRB
  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: ESO-NTT optical observations
  25. GRB 240914A: ESO-NTT optical observations
  26. EP240913a: Swift/XRT detection of an X-ray source within the EP/WXT error circle
  27. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  28. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  29. GRB 240905E: further NOT optical observations
  30. EP240913a: A GRB Event
  31. GRB 240913B: Fermi GBM Final Real-time Localization
  32. GRB 240911A: LCO optical observations
  33. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  34. Fermi Gamma-ray Burst Monitor trigger 747837485/240912526 is not a GRB
  35. GRB 240912A: Swift/UVOT Detection
  36. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  37. GRB 240912A: SVOM/GRM observation
  38. GRB 240911A: Swift-XRT observations
  39. Fermi GRB 240913A: Global MASTER-Net observations report
  40. GRB 240913A: Fermi GBM Final Real-time Localization
  41. GRB 240912A: J-band observations with WINTER
  42. GRB 240912A: Swift-XRT refined Analysis
  43. GRB 240912A: Fermi GBM Observation
  44. Swift GRB 240912A: Global MASTER-Net observations report
  45. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  46. GRB 240911A: Tiled Swift observations
  47. Fermi Gamma-ray Burst Monitor trigger 747839931/240912555 is not a GRB
  48. GRB 240912A : INTEGRAL SPI ACS LIGHT CURVE
  49. GRB 240912B: Fermi GBM Final Real-time Localization
  50. GRB 240912A: NOT optical spectroscopy
  51. GRB 240912A: Enhanced Swift-XRT position
  52. GRB 240912A: Redshift from OSIRIS+/GTC
  53. GRB 240910A: Redshift from OSIRIS+/GTC
  54. GRB 240912A: Swift detection of a burst with an optical counterpart
  55. GRB 240912A: Fermi GBM Final Real-time Localization
  56. GRB 240910A: Fermi GBM Observation
  57. GRB 240910A: NOT optical observations
  58. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  59. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  60. GRB 240910A: JinShan optical observations
  61. GRB 240910A: GOTO candidate optical counterpart
  62. GRB 240710A: SVOM/GRM observation
  63. GRB 240910A: Swift ToO observations
  64. IPN triangulation of GRB 240905B (short)
  65. GRB 240825A: 7DT Optical Upper Limit
  66. GRB 240905E: SVOM/VT optical observations
  67. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  68. GRB 240910A: GRBAlpha detection
  69. GRB 240910B: Fermi GBM Final Real-time Localization
  70. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  71. GRB 240910A: SVOM/GRM observation
  72. EP240908a: Mondy and AbAO follow-up observations
  73. Fermi GRB 240910A: Global MASTER-Net observations report
  74. GRB 240910A: Fermi GBM Final Real-time Localization
  75. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  76. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  77. GRB 240905B: Fermi GBM Observation
  78. GRB 240905B: GOTO optical upper limits
  79. EP240908a: EP detection of a fast X-ray transient
  80. Fermi GRB 240908A: Global MASTER-Net observations report
  81. GRB 240908A: Fermi GBM Final Real-time Localization
  82. GRB 240801A: SVOM/GRM observation
  83. GRB 240905E: GIT optical upper limit
  84. GRB 240905B: Swift-XRT observations
  85. GRB 240905E: Gaoyazi/GOT optical upper limits
  86. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  87. GRB 240905B: Fermi-LAT detection
  88. GRB 240905B: Swift ToO observations
  89. GRB 240905E: J-band observations with WINTER
  90. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  91. GRB 240905E: AKO Optical Upper Limit
  92. GRB 240905E: SVOM/C-GFT optical upper limit
  93. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  94. Fermi GRB 240905D: Global MASTER-Net observations report
  95. Fermi GRB 240905A: Global MASTER-Net observations report
  96. GRB 240905E: NOT optical upper limits
  97. GRB 240905E: REM optical/NIR upper limits
  98. GRB 240902B: AstroSat CZTI detection of a long burst
  99. GRB 240905E: Swift-XRT refined Analysis
  100. GRB 240902A: AstroSat CZTI detection of a long burst

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