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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"

24449 results found.

  1. GRB 250129A: NOT optical observations and redshift confirmation
  2. GRB 250129A: VLT/X-shooter redshift of z = 2.151
  3. Swift GRB 250129A: Global MASTER-Net observations report
  4. Fermi GRB 250128B: Global MASTER-Net observations report
  5. GRB 250129A: Swift detection of a burst with an optical counterpart
  6. Swift GRB 250129A: Global MASTER-Net OT detection
  7. GRB 250128B: Fermi GBM Observation
  8. Swift GRB 250128B: Global MASTER-Net observations report
  9. EP250125a: Upper limits from Swift/BAT-GUANO
  10. GRB 250128B: Swift detection of a short burst
  11. GRB 250128B: Fermi GBM Final Real-time Localization
  12. GRB 250127A: Swift-XRT observations
  13. Fermi-LAT Gamma-ray Observations of IceCube-250102A
  14. Fermi GRB 250128A: Global MASTER-Net observations report
  15. GRB 250128A: Fermi GBM Final Real-time Localization
  16. GRB 250117A: Fermi GBM Observation
  17. Fermi GRB 250127B: Global MASTER-Net observations report
  18. Fermi-LAT Gamma-ray Observations of IceCube-250101A
  19. GRB 250127B: Fermi GBM Final Real-time Localization
  20. IPN triangulation of GRB 250119C
  21. GRB 250127A: LCO optical upper limit
  22. GRB 241223A: cubesat Avion detection
  23. GRB 250127A: SVOM detection of a long burst
  24. GRB 250126A: CALET Gamma-Ray Burst Monitor detection
  25. EP250125A: Non-detection from Fermi-GBM Observations
  26. GRB 250126A: BALROG localization (Fermi Trigger 759560335 / GRB 250126208)
  27. GRB 250126A: Fermi GBM Final Real-time Localization
  28. GECAM-A detection of a bright burst from SGR 1E1841-045
  29. GRB 250118A: Fermi GBM Observation
  30. EP250125a: REM optical counterpart detection
  31. GRB 250119C: Fermi GBM Observation
  32. EP250125a: Gemini-South optical afterglow discovery and redshift z = 2.89
  33. The EP-WXT trigger 01709130758 is a false trigger
  34. The EP-WXT trigger 01709130758 is a false trigger
  35. GRB 250121A: Swift/BAT-GUANO localization skymap of a burst
  36. IPN triangulation of a bright burst from SGR 1E1841-045
  37. GRB 250121A: CALET Gamma-Ray Burst Monitor detection
  38. Konus-Wind detection of GRB 250118B
  39. GRB 250121A: Fermi GBM Observation
  40. IPN triangulation of GRB 250118B
  41. Konus-Wind detection of GRB 250119B
  42. IPN triangulation of GRB 250119B
  43. GRB 250122A: Fermi GBM Final Real-time Localization
  44. Improved IPN triangulation of GRB 250107C
  45. GRB 250114A: Swift-BAT refined analysis
  46. GRB 250121A: Fermi-LAT detection
  47. GRB 250119C: Swift/BAT-GUANO localization skymap of a short burst
  48. GRB 250119B: Swift/BAT-GUANO localization skymap of a long burst
  49. GRB 250121A: Fermi GBM Final Real-time Localization
  50. Fermi-LAT Gamma-ray Observations of IceCube-241224A
  51. GRB 250118A: Swift/BAT-GUANO localization skymap of a short burst
  52. GRB 250119B: Fermi GBM Observation
  53. EP250108a/AT2025kg: 1.3m DFOT Optical observations
  54. Konus-Wind detection of GRB 250117A
  55. IPN triangulation of GRB 250117A (short)
  56. GRB 250119B: INTEGRAL/SPI-ACS detection
  57. LIGO/Virgo/KAGRA S250119cv: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
  58. EP 250108A: Late-time optical observation by LCO
  59. LIGO/Virgo/KAGRA S250105bn: 1 counterpart neutrino candidate event from an IceCube neutrino search
  60. LIGO/Virgo/KAGRA S250119cv: Updated NED Galaxies in the Localization Volume
  61. LIGO/Virgo/KAGRA S250119cv: Updated Sky localization and EM Bright Classification
  62. GRB 250119C: Fermi GBM Final Real-time Localization
  63. LIGO/Virgo/KAGRA S250119cv: NED Galaxies in the Localization Volume
  64. GRB 250117A: Swift/BAT-GUANO localization skymap of a short burst
  65. LIGO/Virgo/KAGRA S250119cv: Identification of a GW compact binary merger candidate
  66. LIGO/Virgo/KAGRA S250119ag: Updated Sky localization
  67. GRB 250117A: GECAM observation of a short burst
  68. LIGO/Virgo/KAGRA S250118dp: Updated Sky localization
  69. GRB 250119B: BALROG localization (Fermi Trigger 758968026 / GRB 250119352)
  70. GRB 250119B: Fermi GBM Final Real-time Localization
  71. LIGO/Virgo/KAGRA S250119ag: Identification of a GW compact binary merger candidate
  72. GRB 250119A: Fermi GBM Final Real-time Localization
  73. GRB 250118A: Fermi GBM Final Real-time Localization
  74. LIGO/Virgo/KAGRA S250118dp: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo/KAGRA S250118t: Updated Sky localization
  76. LIGO/Virgo/KAGRA S250118az: Identification of a GW compact binary merger candidate
  77. LIGO/Virgo/KAGRA S250118t: Identification of a GW compact binary merger candidate
  78. Konus-Wind detection of GRB 250116A
  79. GRB 250116A: INTEGRAL/SPI-ACS and PICsIT detection
  80. GRB 250116A: Fermi-LAT detection
  81. GRB 250116A: Fermi GBM Observation of an Extremely Interesting Burst
  82. GRB 250114B: Swift-XRT afterglow detection
  83. GRB 250114B: SVOM/VT upper limit
  84. LIGO/Virgo/KAGRA S250114ax: Updated NED Galaxies in the Localization Volume
  85. GRB 250101A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations and rebrightening.
  86. LIGO/Virgo/KAGRA S250114ax: Updated Sky localization
  87. Konus-Wind detection of GRB 250113A
  88. IPN triangulation of GRB 250113A
  89. GRB 250114B: Liverpool Telescope optical upper limit
  90. LIGO/Virgo/KAGRA S250114ax: GLADEnet Completeness: Potential Host Galaxies in the 90% Credible Volume
  91. GRB 250114B : MITSuME Akeno optical afterglow candidate detection
  92. GRB 250114B: Swift-XRT observations
  93. GRB 250114B: OHP/T193 optical upper limit
  94. GRB 250114A: Swift-XRT refined Analysis
  95. Integral GRB250114.55: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S250114ax: NED Galaxies in the Localization Volume
  97. GRB 250113A: INTEGRAL/SPI-ACS detection
  98. GRB 250114A: VLT/X-shooter spectroscopic redshift z = 4.732
  99. LIGO/Virgo/KAGRA S250114ax: Identification of a GW compact binary merger candidate
  100. Swift GRB250114A: Global MASTER-Net OT detection

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