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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"

45763 results found.

  1. IceCube Alert 241016.04: Global MASTER-Net observations report
  2. GRB 241010A: Swift-BAT refined analysis
  3. GRB 241013B: Fermi GBM Observation
  4. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  5. GRB 241013A: Fermi GBM Observation
  6. GRB 240916A: radio detection with the VLA
  7. GRB241013A: REM observations
  8. GRB 241009A: LCO optical upper limits
  9. GRB 241013B: SVOM/GRM observation
  10. Fermi GRB 241013B: Global MASTER-Net observations report
  11. Integral GRB241013.04: Global MASTER-Net observations report
  12. GRB 241013B: Fermi GBM Final Real-time Localization
  13. GRB 241013A: a long GRB detected by INTEGRAL
  14. GRB 241013A: Fermi GBM Final Real-time Localization
  15. LIGO/Virgo/KAGRA S241009em: Updated Sky localization
  16. LIGO/Virgo/KAGRA S241011k: Updated Sky localization
  17. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  18. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  19. Fermi Gamma-ray Burst Monitor GRB trigger 750372658/241011869 (GRB 241011A) is not a GRB
  20. GRB 241011A: Fermi GBM Final Real-time Localization
  21. GRB 241009A: GRANDMA optical upper limits
  22. GRB 241009A: Swift-XRT afterglow detection
  23. GRB 241010A: JinShan optical observations and potential host galaxy
  24. GRB 241006A: ATCA Radio Upper Limits
  25. GRB 241010A: Swift-XRT refined Analysis
  26. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  27. Fermi trigger No 750211959: Global MASTER-Net observations report
  28. Fermi Gamma-ray Burst Monitor trigger 750303285/241011066 is not a GRB
  29. Fermi Gamma-ray Burst Monitor trigger 750291012/241010924 is not a GRB
  30. Swift GRB 241010A: Global MASTER-Net observations report
  31. Fermi trigger No 750291012: Global MASTER-Net observations report
  32. GRB 241010A: J-band observations with WINTER
  33. LIGO/Virgo/KAGRA S241009an: Updated Sky localization
  34. Fermi GRB 241010B: Global MASTER-Net observations report
  35. GRB 241010B: Fermi GBM Final Real-time Localization
  36. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  37. GRB 241010A: Enhanced Swift-XRT position
  38. GRB 241010A: LCO optical observations
  39. GRB 241010A: Swift detection of a burst with an optical counterpart
  40. Fermi-LAT Gamma-ray Observations of IceCube-241006A
  41. GRB 241006A: Swift-BAT refined analysis
  42. GRB 241009A: Swift ToO observations
  43. LIGO/Virgo/KAGRA S241009l: Updated Sky localization
  44. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  45. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  46. GRB 241008A: Fermi GBM Observation
  47. GRB 241008A: Fermi-LAT detection
  48. GRB 241002B: Swift-XRT afterglow detection
  49. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  50. GRB 241002A: NOT optical upper limits
  51. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  52. Fermi GRB 241008A: Global MASTER-Net observations report
  53. GRB 241008A: BALROG localization (Fermi Trigger 750117609 / GRB 241008917)
  54. GRB 241008A: Fermi GBM Final Real-time Localization
  55. IceCube-241006A: No candidates from the Zwicky Transient Facility
  56. GRB 241006A: GRANDMA optical upper limits
  57. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  58. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  59. Fermi-LAT Gamma-ray Observations of NuEm-240926A
  60. GRB 240910A: LBT optical observations
  61. EP trigger ID 01709065118: KAIT confirmation of the stellar flare
  62. GRB 241006A: Swift-XRT refined Analysis
  63. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  64. GRB 241006A: PRIME near-infrared upper limits
  65. GRB 241006A: Swift/UVOT Upper Limits
  66. GRB 241006A: SVOM/VT follow-up and optical upper limit
  67. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  68. IceCube Alert 241006.94: Global MASTER-Net observations report
  69. GRB 241001A: Swift-XRT afterglow detection
  70. GRB 241006A: Enhanced Swift-XRT position
  71. IceCube-241006A - IceCube observation of a high-energy neutrino candidate track-like event
  72. GRB 241006A: Swift detection of a burst
  73. Swift GRB241006.91: Global MASTER-Net observations report
  74. GRB 240930B: SVOM/C-GFT optical upper limit
  75. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  76. LIGO/Virgo/KAGRA S241005bo: Retraction of GW compact binary merger candidate
  77. Fermi trigger No 749721670: Global MASTER-Net observations report
  78. GRB 241004A: SVOM/GRM observation
  79. EP trigger ID 01709065118: the X-ray transient is likely a stellar flare event
  80. GRB 240930B / EP 240930a: SVOM/GRM observation
  81. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  82. GRB 241002B: PRIME near-infrared detection in 2nd epoch
  83. GRB 241002B: Fermi GBM Observation
  84. Fermi trigger No 749735279: Global MASTER-Net observations report
  85. Fermi trigger No 749630753: Global MASTER-Net observations report
  86. Fermi trigger No 749693019: Global MASTER-Net observations report
  87. GRB 241002B: Swift-XRT observations
  88. GRB 241002C: SVOM/C-GFT optical upper limit
  89. GRB 241002A: Swift-BAT refined analysis
  90. GRB 241002B: Swift/BAT-GUANO localization skymap of a burst
  91. GRB 241002B: Swift ToO observations
  92. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  93. Konus-Wind detection of GRB 240926A
  94. GRB 241002B: PRIME near-infrared detection
  95. LIGO/Virgo/KAGRA S240925n: NED Galaxies in the Localization Volume
  96. GRB 241002C: Swift ToO observations
  97. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  98. IPN triangulation of GRB 240930B / EP 240930a
  99. GRB 241001A : SVOM/VT optical detection
  100. GRB 241002B: GOTO24gpc/AT 2024xbg follow-up observations update

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