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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"

28302 results found.

  1. EP240806A: Liverpool Telescope optical follow-up observations
  2. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  3. EP240807a: EP-WXT detection of a fast X-ray transient
  4. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  5. GRB 240805B: GIT optical upper limit
  6. GRB 240805B: Swift-BAT refined analysis
  7. GRB 240805A: Swift-BAT refined analysis
  8. EP240806a: LCOGT optical counterpart detection
  9. GRB 240805B Bassano Bresciano Observatory upper limit
  10. GRB240805A: Fermi GBM Observation
  11. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  12. EP240806a: EP-FXT detection of the X-ray emission
  13. GRB 240626B: VZLUSAT-2 detection
  14. GRB 240624B: VZLUSAT-2 detection
  15. GRB 240619C: VZLUSAT-2 detection
  16. EP 240806A: LCO optical observations
  17. EP240806a: EP-WXT detection of a fast X-ray transient
  18. GRB 240805B: Optical detection with 1.6m Mephisto
  19. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  20. GRB 240805B: Swift-XRT refined Analysis
  21. GRB 240805B: Swift/UVOT Upper Limits
  22. GRB 240805A: Swift/UVOT Upper Limits
  23. GRB 240805B: BTA optical afterglow candidate
  24. GRB 240805B: Enhanced Swift-XRT position
  25. GRB 240805B: LCOGT Optical Upper Limits
  26. GRB 240805B: JinShan optical upper limits
  27. EP240801a: BTA BVRI photometry
  28. GRB 240805A: Swift-XRT refined Analysis
  29. EP240804a: GSP detects optical candidate counterpart
  30. GRB 240805B: Swift detection of a burst
  31. GRB 240805A: INTEGRAL spectral analysis
  32. EP240801a: Continued optical observations at ZTSh (CraO)
  33. EP240804a: LCOGT optical counterpart detection
  34. EP240804a: NOT optical counterpart detection
  35. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  36. EP240802a: Montarrenti Observatory optical upper limit
  37. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  38. EP240802A: Bassano Bresciano Observatory upper limit
  39. GRB 240802A: SVOM/GRM observation
  40. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  41. Fermi trigger No 744278264: Global MASTER-Net observations report
  42. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  43. GRB 240802A: AstroSat CZTI detection of a long burst
  44. EP240801a: further SAO RAS optical observations
  45. EP240801a: optical observations at CrAO and AbAO
  46. EP240801a: Leavitt Observatory optical observations
  47. EP240801a: SAO RAS optical observations
  48. EP240801a: JinShan optical observations
  49. GRB 240727C: SVOM/GRM observation
  50. EP240801a: follow-up observation with LCOGT
  51. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  52. GRB 240730A: Swift-BAT refined analysis
  53. EP240801a: GSP follow-up observations of the candidate counterpart
  54. EP240801a: Kinder follow-up observations of the candidate counterpart
  55. EP240801a: GMG observation
  56. EP240801a: TRT optical counterpart detection
  57. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  58. GRB 240801B: AstroSat CZTI detection of a bright long burst
  59. GRB 240801A: Fermi GBM Final Real-time Localization
  60. GRB 240730C: AstroSat CZTI detection of a long burst
  61. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  62. GRB240730A: BOOTES-5/JGT early optical upper limit
  63. Swift GRB 240730A: Global MASTER-Net observations report
  64. GRB 240730A: Swift-XRT refined Analysis
  65. GRB 240715A: Swift-XRT afterglow detection
  66. GRB 240730A: Swift/UVOT Upper Limits
  67. GRB 240730A: Enhanced Swift-XRT position
  68. GRB 240730A: Swift detection of a burst
  69. GRB 240727A: Swift-BAT refined analysis
  70. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  71. GRB 240727A: observations of optical counterpart.
  72. GRB 240727B: Swift-XRT observations
  73. Fermi GRB 240727A: Global MASTER-Net observations report
  74. GRB 240727A: Swift/UVOT detection
  75. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  76. GRB 240727A: NOT optical observation
  77. GRB 240727A: JinShan optical upper limits
  78. GRB 240727A Bassano Bresciano Observatory upper limit
  79. GRB 240727C: AstroSat CZTI detection of a long burst
  80. GRB 240727A: Swift-XRT refined Analysis
  81. Fermi GRB 240726A: Global MASTER-Net observations report
  82. GRB 240727A: Enhanced Swift-XRT position
  83. GRB 240727B: Fermi GBM Observation
  84. GRB240529A: VIRT optical transient detection
  85. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  86. GRB 240726A: SVOM/GRM observation
  87. GRB 240726B: AstroSat CZTI detection of a short burst
  88. GRB240727A: Skynet Optical Afterglow Observations
  89. GRB 240727A: TRT optical afterglow detection
  90. GRB 240727A: Swift detection of a burst
  91. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  92. Fermi-LAT gamma-ray observations of IceCube-240725A
  93. Swift Trigger 1244778 is not a GRB
  94. IceCube-240721A: Two candidates from the Zwicky Transient Facility
  95. GRB 240720A: Swift-BAT refined analysis
  96. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  97. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  98. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  99. Fermi-LAT gamma-ray observations of IceCube-240721A
  100. GRB 240720B: SVOM/GRM observation

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