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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"

21944 results found.

  1. GRB 240805B: Optical detection with 1.6m Mephisto
  2. EP240804a: BOOTES-6/DPRT optical detection
  3. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  4. GRB 240805B: Swift/UVOT Upper Limits
  5. GRB 240805A: Swift/UVOT Upper Limits
  6. GRB 240805B: BTA optical afterglow candidate
  7. GRB 240805B: Enhanced Swift-XRT position
  8. GRB 240805B: LCOGT Optical Upper Limits
  9. GRB 240805B: JinShan optical upper limits
  10. EP240801a: BTA BVRI photometry
  11. GRB 240805A: Swift-XRT refined Analysis
  12. GRB 240805B: Swift detection of a burst
  13. GRB 240805A: Fermi-LAT detection
  14. EP240801a: Continued optical observations at ZTSh (CraO)
  15. GRB 240805A: A long GRB detected by INTEGRAL
  16. EP240804a: NOT optical counterpart detection
  17. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  18. GRB 240805A: Fermi GBM Final Real-time Localization
  19. EP240802a: Montarrenti Observatory optical upper limit
  20. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  21. EP240802A: Bassano Bresciano Observatory upper limit
  22. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  23. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  24. EP240801a: further SAO RAS optical observations
  25. EP240801a: optical observations at CrAO and AbAO
  26. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  27. EP240801a: Leavitt Observatory optical observations
  28. EP240801a: SAO RAS optical observations
  29. EP240801a: JinShan optical observations
  30. GRB 240727C: SVOM/GRM observation
  31. EP240801a: follow-up observation with LCOGT
  32. EP240801a: Kinder follow-up observations of the candidate counterpart
  33. EP240801a: GMG observation
  34. EP240801a: TRT optical counterpart detection
  35. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  36. GRB 240730C: AstroSat CZTI detection of a long burst
  37. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  38. GRB240730A: BOOTES-5/JGT early optical upper limit
  39. GRB 240727C: GRBAlpha detection
  40. GRB 240730A: Swift/UVOT Upper Limits
  41. GRB 240730A: Enhanced Swift-XRT position
  42. GRB 240730A: Swift detection of a burst
  43. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  44. GRB 240727A: observations of optical counterpart.
  45. GRB 240727B: Swift-XRT observations
  46. Fermi GRB 240727A: Global MASTER-Net observations report
  47. GRB 240727A: Swift/UVOT detection
  48. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  49. GRB 240727A: NOT optical observation
  50. GRB 240727A: JinShan optical upper limits
  51. GRB 240727A Bassano Bresciano Observatory upper limit
  52. GRB 240720B: GRBAlpha detection
  53. GRB 240718A: GRBAlpha detection
  54. GRB 240710B: GRBAlpha detection
  55. GRB 240627A: GRBAlpha detection
  56. GRB 240727A: Enhanced Swift-XRT position
  57. GRB240529A: VIRT optical transient detection
  58. GRB 240726A: SVOM/GRM observation
  59. GRB240727A: Skynet Optical Afterglow Observations
  60. GRB 240727A: TRT optical afterglow detection
  61. GRB 240727A: Swift detection of a burst
  62. GRB 240726A: AstroSat CZTI detection of a short burst
  63. Swift Trigger 1244778 is not a GRB
  64. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  65. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  66. GRB 240720B: SVOM/GRM observation
  67. GRB 240720A: AstroSat CZTI detection
  68. Konus-Wind detection of GRB 240718A
  69. Fermi GRB 240718A: Global MASTER-Net observations report
  70. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  71. GRB 240718A: Fermi-LAT Detection
  72. GRB 240718A: SVOM/GRM observation
  73. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  74. GRB 240715A: Swift/UVOT observations of the XRT sources.
  75. GRB240713A: Swift/UVOT Upper LImits
  76. Konus-Wind detection of GRB 240715A
  77. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  78. GRB 240712A: Swift-XRT refined Analysis
  79. GRB 240713A: LAST optical upper limit
  80. LIGO/Virgo/KAGRA S240716b: Identification of a GW compact binary merger candidate
  81. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  82. GRB240715A: GRANDMA Optical Upper Limits
  83. GW s240422ed: Swift UVOT follow-up
  84. GRB 240712A: Swift/UVOT Upper Limits
  85. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  86. The EP-WXT source triggered on July 14th is likely a flaring star
  87. GRB 240713A: J-band upper limit from WINTER
  88. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  89. GRB 240713A: JinShan optical upper limits
  90. GRB 240713A: OHP/T120 optical upper limit
  91. GRB 240713B: AstroSat CZTI detection of a long burst
  92. GRB240713A: Optical upper limit with Kinder observations
  93. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  94. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  95. EP240708a: GSP optical upper limit
  96. GRB 240712A: Swift detection of a burst
  97. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  98. LIGO/Virgo/KAGRA S240627by: Updated Sky localization and EM Bright Classification
  99. EP240708a: NOT optical observations
  100. EP240708a: SVOM/C-GFT optical upper limit

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