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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"

19722 results found.

  1. GRB 240809A: GIT afterglow observations
  2. GRB 240809A: Swift/UVOT Detection
  3. IPN triangulation of GRB 240807A / EP 240807a
  4. X-ray Transient EP240807a: PRIME near-infrared upper limits
  5. GRB 240809A: JinShan optical observations
  6. GRB 240809A: Enhanced Swift-XRT position
  7. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  8. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  9. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  10. EP240807a: STEP/T80S optical limits
  11. EP240806A: Liverpool Telescope optical follow-up observations
  12. The EP-WXT trigger 01709018832 on August 7th is likely a flaring star
  13. EP240807a: EP-WXT detection of a fast X-ray transient
  14. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  15. GRB 240805B: GIT optical upper limit
  16. EP240806a: LCOGT optical counterpart detection
  17. GRB 240805B Bassano Bresciano Observatory upper limit
  18. GRB240805A: Fermi GBM Observation
  19. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  20. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  21. EP 240806A: LCO optical observations
  22. EP240806a: EP-WXT detection of a fast X-ray transient
  23. GRB 240805B: Optical detection with 1.6m Mephisto
  24. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  25. GRB 240805B: Swift/UVOT Upper Limits
  26. GRB 240805A: Swift/UVOT Upper Limits
  27. GRB 240805B: BTA optical afterglow candidate
  28. GRB 240805B: Enhanced Swift-XRT position
  29. GRB 240805B: LCOGT Optical Upper Limits
  30. GRB 240805B: JinShan optical upper limits
  31. EP240801a: BTA BVRI photometry
  32. GRB 240805A: Swift-XRT refined Analysis
  33. GRB 240805B: Swift detection of a burst
  34. EP240801a: Continued optical observations at ZTSh (CraO)
  35. EP240804a: NOT optical counterpart detection
  36. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  37. EP240802a: Montarrenti Observatory optical upper limit
  38. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  39. EP240802A: Bassano Bresciano Observatory upper limit
  40. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  41. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  42. GRB 240802A: AstroSat CZTI detection of a long burst
  43. EP240801a: further SAO RAS optical observations
  44. EP240801a: optical observations at CrAO and AbAO
  45. EP240801a: Leavitt Observatory optical observations
  46. EP240801a: SAO RAS optical observations
  47. EP240801a: JinShan optical observations
  48. GRB 240727C: SVOM/GRM observation
  49. EP240801a: follow-up observation with LCOGT
  50. EP240801a: Kinder follow-up observations of the candidate counterpart
  51. EP240801a: GMG observation
  52. EP240801a: TRT optical counterpart detection
  53. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  54. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  55. GRB 240730A: Swift/UVOT Upper Limits
  56. GRB 240730A: Enhanced Swift-XRT position
  57. GRB 240730A: Swift detection of a burst
  58. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  59. GRB 240727A: observations of optical counterpart.
  60. GRB 240727B: Swift-XRT observations
  61. GRB 240727A: Swift/UVOT detection
  62. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  63. GRB 240727A: NOT optical observation
  64. GRB 240727A: JinShan optical upper limits
  65. GRB 240727A Bassano Bresciano Observatory upper limit
  66. GRB 240727C: AstroSat CZTI detection of a long burst
  67. GRB 240727A: Swift-XRT refined Analysis
  68. GRB 240727A: Enhanced Swift-XRT position
  69. GRB240529A: VIRT optical transient detection
  70. GRB 240727B: Swift ToO observations
  71. GRB 240726A: SVOM/GRM observation
  72. GRB 240727B: AstroSat CZTI detection
  73. GRB240727A: Skynet Optical Afterglow Observations
  74. GRB 240727A: TRT optical afterglow detection
  75. GRB 240727A: Swift detection of a burst
  76. Swift Trigger 1244778 is not a GRB
  77. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  78. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  79. GRB 240720B: SVOM/GRM observation
  80. GRB 240720A: AstroSat CZTI detection
  81. GRB 240718A: SVOM/GRM observation
  82. GRB 240716A: GECAM-B detection of a long burst
  83. SVOM/GRM In-Flight Trigger of GRB 240716A
  84. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  85. GRB 240715A: Swift/UVOT observations of the XRT sources.
  86. GRB240713A: Swift/UVOT Upper LImits
  87. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  88. GRB 240712A: Swift-XRT refined Analysis
  89. GRB 240713A: LAST optical upper limit
  90. GRB 240715A: Swift ToO observations
  91. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  92. GRB240715A: GRANDMA Optical Upper Limits
  93. GW s240422ed: Swift UVOT follow-up
  94. GRB 240712A: Swift/UVOT Upper Limits
  95. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  96. The EP-WXT source triggered on July 14th is likely a flaring star
  97. GRB 240713A: Tiled Swift observations
  98. GRB 240713A: J-band upper limit from WINTER
  99. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  100. GRB 240713A: JinShan optical upper limits

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