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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"

19718 results found.

  1. GRB 240809A: JinShan optical observations
  2. GRB 240809A: Enhanced Swift-XRT position
  3. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  4. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  5. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  6. EP240807a: STEP/T80S optical limits
  7. EP240806A: Liverpool Telescope optical follow-up observations
  8. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  9. EP240807a: EP-WXT detection of a fast X-ray transient
  10. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  11. GRB 240805B: GIT optical upper limit
  12. EP240806a: LCOGT optical counterpart detection
  13. GRB 240805B Bassano Bresciano Observatory upper limit
  14. GRB240805A: Fermi GBM Observation
  15. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  16. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  17. EP 240806A: LCO optical observations
  18. EP240806a: EP-WXT detection of a fast X-ray transient
  19. GRB 240805B: Optical detection with 1.6m Mephisto
  20. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  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. GRB 240805B: Swift detection of a burst
  30. EP240801a: Continued optical observations at ZTSh (CraO)
  31. EP240804a: NOT optical counterpart detection
  32. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  33. EP240802a: Montarrenti Observatory optical upper limit
  34. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  35. EP240802A: Bassano Bresciano Observatory upper limit
  36. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  37. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  38. GRB 240802A: AstroSat CZTI detection of a long burst
  39. EP240801a: further SAO RAS optical observations
  40. EP240801a: optical observations at CrAO and AbAO
  41. EP240801a: Leavitt Observatory optical observations
  42. EP240801a: SAO RAS optical observations
  43. EP240801a: JinShan optical observations
  44. GRB 240727C: SVOM/GRM observation
  45. EP240801a: follow-up observation with LCOGT
  46. EP240801a: Kinder follow-up observations of the candidate counterpart
  47. EP240801a: GMG observation
  48. EP240801a: TRT optical counterpart detection
  49. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  50. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  51. GRB 240730A: Swift/UVOT Upper Limits
  52. GRB 240730A: Enhanced Swift-XRT position
  53. GRB 240730A: Swift detection of a burst
  54. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  55. GRB 240727A: observations of optical counterpart.
  56. GRB 240727B: Swift-XRT observations
  57. GRB 240727A: Swift/UVOT detection
  58. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  59. GRB 240727A: NOT optical observation
  60. GRB 240727A: JinShan optical upper limits
  61. GRB 240727A Bassano Bresciano Observatory upper limit
  62. GRB 240727C: AstroSat CZTI detection of a long burst
  63. GRB 240727A: Swift-XRT refined Analysis
  64. GRB 240727A: Enhanced Swift-XRT position
  65. GRB240529A: VIRT optical transient detection
  66. GRB 240727B: Swift ToO observations
  67. GRB 240726A: SVOM/GRM observation
  68. GRB 240727B: AstroSat CZTI detection
  69. GRB240727A: Skynet Optical Afterglow Observations
  70. GRB 240727A: TRT optical afterglow detection
  71. GRB 240727A: Swift detection of a burst
  72. Swift Trigger 1244778 is not a GRB
  73. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  74. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  75. GRB 240720B: SVOM/GRM observation
  76. GRB 240720A: AstroSat CZTI detection
  77. GRB 240718A: SVOM/GRM observation
  78. GRB 240716A: GECAM-B detection of a long burst
  79. SVOM/GRM In-Flight Trigger of GRB 240716A
  80. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  81. GRB 240715A: Swift/UVOT observations of the XRT sources.
  82. GRB240713A: Swift/UVOT Upper LImits
  83. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  84. GRB 240712A: Swift-XRT refined Analysis
  85. GRB 240713A: LAST optical upper limit
  86. GRB 240715A: Swift ToO observations
  87. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  88. GRB240715A: GRANDMA Optical Upper Limits
  89. GW s240422ed: Swift UVOT follow-up
  90. GRB 240712A: Swift/UVOT Upper Limits
  91. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  92. The EP-WXT source triggered on July 14th is likely a flaring star
  93. GRB 240713A: Tiled Swift observations
  94. GRB 240713A: J-band upper limit from WINTER
  95. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  96. GRB 240713A: JinShan optical upper limits
  97. GRB 240713A: OHP/T120 optical upper limit
  98. GRB240713A: Optical upper limit with Kinder observations
  99. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  100. GRB 240712A: Swift detection of a burst

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