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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

12108 results found.

  1. Konus-Wind detection of GRB 240802A (EP240802a)
  2. Konus-Wind detection of GRB 240805A
  3. GRB 240805B Bassano Bresciano Observatory upper limit
  4. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  5. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  6. GRB 240805B: Swift-XRT refined Analysis
  7. Fermi trigger No 744544656: Global MASTER-Net observations report
  8. GRB 240805A: Fermi-LAT detection
  9. GRB 240805A: INTEGRAL spectral analysis
  10. EP240801a: Continued optical observations at ZTSh (CraO)
  11. EP240804a: VLT/X-shooter spectroscopic redshift
  12. GRB 240805A: A long GRB detected by INTEGRAL
  13. EP240804a: NOT optical counterpart detection
  14. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  15. GRB 240805A: Fermi GBM Final Real-time Localization
  16. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  17. GRB 240802A: AstroSat CZTI detection of a long burst
  18. EP240801a: optical observations at CrAO and AbAO
  19. EP240801a: Leavitt Observatory optical observations
  20. GRB 240801B: AstroSat CZTI detection of a bright long burst
  21. Fermi GRB 240801A: Global MASTER-Net observations report
  22. GRB 240730C: AstroSat CZTI detection of a long burst
  23. GRB 240731A: Fermi GBM Final Localization
  24. GRB 240731A: AstroSat CZTI detection
  25. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  26. Fermi GRB 240727A: Global MASTER-Net observations report
  27. GRB 240727A: Swift/UVOT detection
  28. GRB 240727A: Correction to time in GCN36960
  29. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  30. GRB 240727A Bassano Bresciano Observatory upper limit
  31. GRB 240727C: AstroSat CZTI detection of a long burst
  32. GRB 240727A: Swift-XRT refined Analysis
  33. GRB 240720B: GRBAlpha detection
  34. Fermi GRB 240726A: Global MASTER-Net observations report
  35. GRB 240727B: AstroSat CZTI detection
  36. GRB 240726B: AstroSat CZTI detection of a short burst
  37. GRB 240727A: Swift detection of a burst
  38. GRB 240726A: AstroSat CZTI detection of a short burst
  39. Fermi-LAT gamma-ray observations of IceCube-240725A
  40. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  41. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  42. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  43. Fermi-LAT gamma-ray observations of IceCube-240721A
  44. Fermi trigger No 743219692: Global MASTER-Net observations report
  45. IceCube Alert 240721.68: Global MASTER-Net observations report
  46. GRB 240720B: AstroSat CZTI detection of a short burst
  47. Fermi GRB 240720A: Global MASTER-Net observations report
  48. GRB 240720A: AstroSat CZTI detection
  49. GRB 240720A: Fermi GBM observation
  50. GRB 240720A: Swift detection of a burst
  51. Swift GRB240720.02: Global MASTER-Net observations report
  52. Konus-Wind detection of GRB 240718A
  53. Fermi GRB 240718A: Global MASTER-Net observations report
  54. LAT GRB240718.27: Global MASTER-Net observations report
  55. GRB 240718A: Fermi-LAT Detection
  56. GRB 240712A: Swift-BAT refined analysis
  57. GRB 240716A: GECAM-B detection of a long burst
  58. Fermi-LAT gamma-ray observations of IceCube-cascade-240714A
  59. GRB 240715A: Swift-XRT observations
  60. Konus-Wind detection of GRB 240715A
  61. IPN triangulation of GRB 240715A (short)
  62. The EP-WXT source triggered on July 14th is likely a flaring star
  63. GRB 240713A: JinShan optical upper limits
  64. GRB 240713B: AstroSat CZTI detection of a long burst
  65. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  66. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  67. EP240708a: EP-WXT detection of a fast X-ray transient
  68. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  69. Konus-Wind detection of GRB 240627A
  70. EP240703a and EP240703b: Swift/XRT upper limits
  71. EP240703a: BTA observations
  72. EP240703c: EP-WXT detection of an X-ray transient
  73. EP240703b: EP-WXT detection of a fast X-ray transient
  74. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  75. EP240702a: Swift/XRT upper limit
  76. Fermi GRB 240702A: Global MASTER-Net observations report
  77. EP240702a: EP-WXT detection of a fast X-ray transient
  78. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  79. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  80. Fermi trigger No 741356809: Global MASTER-Net observations report
  81. Fermi GRB 240629A: Global MASTER-Net observations report
  82. Fermi trigger No 741296200: Global MASTER-Net observations report
  83. GRB 240627A: NuSTAR Detection of the long GRB
  84. GRB 240615A: SAI CMO J- band observations
  85. GRB 240627A: AstroSat CZTI detection
  86. EP240625a: GRANDMA Optical Upper Limits
  87. Konus-Wind detection of GRB 240619A
  88. EP240625a: NOT optical counterpart candidate
  89. EP240625a: EP-FXT detection of the X-ray emission
  90. EP240625a: EP-WXT detection of a fast X-ray transient
  91. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  94. Fermi trigger No 740949590: Global MASTER-Net observations report
  95. EP240618a: NOT optical counterpart candidate
  96. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  98. GRB 240619C: NuSTAR automated detection of the GRB
  99. GRB 240615A: NOT optical observations
  100. GRB 240619C: AstroSat CZTI detection

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