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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.

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

24513 results found.

  1. Fermi GRB 240715A: Global MASTER-Net observations report
  2. GRB 240715A: Fermi GBM Observation
  3. GRB240715A: GRANDMA Optical Upper Limits
  4. IPN triangulation of GRB 240715A (short)
  5. The EP-WXT source triggered on July 14th is likely a flaring star
  6. GRB 240715A: Fermi GBM Final Real-time Localization
  7. GRB 240713A: J-band upper limit from WINTER
  8. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  9. GRB 240713A: JinShan optical upper limits
  10. GRB 240713A: OHP/T120 optical upper limit
  11. GRB240713A: X-ray follow-up observation with EP-FXT
  12. GRB 240713B: AstroSat CZTI detection of a long burst
  13. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  14. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  15. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  16. GRB 240711A: Fermi GBM Final Real-time Localization
  17. Fermi trigger No 742405878: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S240627by: Updated Sky localization and EM Bright Classification
  19. Fermi trigger No 742317942: Global MASTER-Net observations report
  20. Fermi GRB 240710A: Global MASTER-Net observations report
  21. GRB 240710A: Fermi GBM Final Real-time Localization
  22. EP240708a: NOT optical observations
  23. EP240708a: SVOM/C-GFT optical upper limit
  24. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  25. GRB 240705A: Fermi GBM Final Real-time Localization
  26. Konus-Wind detection of GRB 240627A
  27. IPN triangulation of GRB 240628B (short)
  28. LIGO/Virgo/KAGRA S240705at: Updated Sky localization
  29. EP240703a and EP240703b: Swift/XRT upper limits
  30. LIGO/Virgo/KAGRA S240705at: Identification of a GW compact binary merger candidate
  31. EP240703a: BTA observations
  32. EP240703a: Liverpool Telescope optical follow-up observations
  33. EP240703a/GRB 240703A: TRT optical candidate likely not real
  34. LIGO/Virgo/KAGRA S240703ad: Updated Sky localization
  35. LIGO/Virgo/KAGRA S240703ad: Identification of a GW compact binary merger candidate
  36. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  37. IPN triangulation of GRB 240627A
  38. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  39. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  40. EP240702a: Swift/XRT upper limit
  41. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  42. Fermi GRB 240702A: Global MASTER-Net observations report
  43. GRB 240702A: Fermi GBM Final Real-time Localization
  44. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  45. Fermi trigger No 741448122: Global MASTER-Net observations report
  46. LIGO/Virgo/KAGRA S240630t: Updated Sky localization
  47. LIGO/Virgo/KAGRA S240629by: Updated Sky localization
  48. LIGO/Virgo/KAGRA S240630t: Identification of a GW compact binary merger candidate
  49. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  50. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  51. Fermi trigger No 741356809: Global MASTER-Net observations report
  52. Fermi GRB 240629A: Global MASTER-Net observations report
  53. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  54. GRB 240629A: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo/KAGRA S240629by: Identification of a GW compact binary merger candidate
  56. Fermi trigger No 741296200: Global MASTER-Net observations report
  57. Fermi trigger No 741251380: Global MASTER-Net observations report
  58. IPN triangulation of GRB 240619C
  59. IceCube-Cascade 240626A: Upper limits from a search for additional neutrino events in IceCube
  60. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  61. GRB 240615A: SAI CMO J- band observations
  62. GRB 240627A: AstroSat CZTI detection
  63. Fermi trigger No 741211696: Global MASTER-Net observations report
  64. LIGO/Virgo/KAGRA S240627by: Identification of a GW compact binary merger candidate
  65. EP240626a: EP-FXT detection of the X-ray emission
  66. GRB 240624A: Swift-BAT refined analysis
  67. Konus-Wind detection of GRB 240619A
  68. Fermi GRB 240625B: Global MASTER-Net observations report
  69. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  70. GRB 240625B: Fermi GBM Final Real-time Localization
  71. GRB 240625A: Fermi GBM Observation
  72. EP240625a: NOT optical counterpart candidate
  73. EP240625a: EP-FXT detection of the X-ray emission
  74. GRB 240624B: GRBAlpha detection
  75. GRB 240625A: Fermi GBM Final Real-time Localization
  76. GRB240624A: Fermi GBM Observation
  77. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  78. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  79. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  80. Swift GRB 240624A: Global MASTER-Net observations report
  81. Fermi GRB 240624A: Global MASTER-Net observations report
  82. GRB 240624B: Fermi GBM Final Real-time Localization
  83. Fermi trigger No 740949590: Global MASTER-Net observations report
  84. GRB 240624A: Fermi GBM Final Real-time Localization
  85. GRB 240624A: Swift detection of a burst
  86. LIGO/Virgo/KAGRA S240623dg: Retraction of GW compact binary merger candidate
  87. LIGO/Virgo/KAGRA S240622h: Updated Sky localization and Source Classification
  88. Fermi trigger No 740744838: Global MASTER-Net observations report
  89. LIGO/Virgo/KAGRA S240621em: Updated Sky localization and Source Classification
  90. LIGO/Virgo/KAGRA S240621dy: Updated Sky localization and Source Classification
  91. LIGO/Virgo/KAGRA S240621eb: Updated Sky localization and Source Classification
  92. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S240621em: Identification of a GW compact binary merger candidate
  94. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  95. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  96. IPN triangulation of GRB 240615A (short)
  97. X-ray transient EP240618a: Fermi/GBM non-detection
  98. GRB 240619A: GRBAlpha detection
  99. EP240618a: Swift/XRT upper limit
  100. EP240617a: tentative Swift/XRT detection of the afterglow

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