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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"

24577 results found.

  1. LIGO/Virgo/KAGRA S230520ae: Identification of a GW compact binary merger candidate: End-to-End Test
  2. GRB 230520B: Fermi GBM Final Real-time Localization
  3. LIGO/Virgo/KAGRA S230520ae: Upper limits from IceCube neutrino search
  4. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  5. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  6. GRB 230518A: Fermi GBM Observation
  7. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  8. LIGO/Virgo S230518h: AGILE/MCAL observations
  9. GRB 230518A: Swift/BAT-GUANO detection
  10. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  11. GRB 230518A: Fermi GBM Final Real-time Localization
  12. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  13. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  14. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  15. LIGO/Virgo S230518h: Global MASTER-Net observations report
  16. LIGO/Virgo/KAGRA S230518h: Updated Sky localization and EM Bright Classification
  17. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S230518h: Upper limits from IceCube neutrino search
  19. LIGO/Virgo/KAGRA S230518h: Identification of a GW compact binary merger candidate
  20. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  21. GRB 230510B: GRBAlpha detection
  22. Fermi trigger No 706014351: Global MASTER-Net observations report
  23. GRB 230517A: BALROG localization (Fermi Trigger 706014351 / GRB 230517462)
  24. GRB 230517A: Fermi GBM Final Real-time Localization
  25. GRB 230510B: Fermi GBM detection
  26. Fermi trigger No 705952199: Global MASTER-Net observations report
  27. GRB 230516A: Fermi GBM Final Real-time Localization
  28. IPN triangulation of GRB 230511D (short)
  29. IPN triangulation of GRB 230512A
  30. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  31. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  32. GRB 230512A: Kitab possible afterglow candidate
  33. GRB 230512A: GRBAlpha detection
  34. GRB 230510A: GRBAlpha detection
  35. GRB 230513A: Fermi GBM Final Real-time Localization
  36. Fermi trigger No 705565670: Global MASTER-Net observations report
  37. Fermi-LAT gamma-ray observations of IceCube-230511A
  38. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  39. GRB 230512A: Swift-XRT observations
  40. IceCube-230511A: Upper limits from a search for additional neutrino events in IceCube
  41. IceCube-Cascade 230511A: Upper limits from a search for additional neutrino events in IceCube
  42. GRB 230512A: GIT optical follow-up ZTF candidates
  43. GRB 230512A: Fermi GBM detection
  44. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  45. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  46. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  47. GRB 230512A: Fermi-LAT detection
  48. GRB 230512A: Fermi GBM Final Localization
  49. GRB 230510A: LCOGT Optical Upper Limit
  50. GRB 230511D: Fermi GBM Final Real-time Localization
  51. IceCube-230511A: IceCube observation of a high-energy neutrino candidate
  52. GRB 230511C: Fermi GBM Final Localization
  53. Fermi trigger No 705503315: Global MASTER-Net observations report
  54. GRB 230511B: Fermi GBM Final Real-time Localization
  55. Fermi trigger No 705496510: Global MASTER-Net observations report
  56. GRB 230511A: Fermi GBM Final Real-time Localization
  57. GRB 230510A: Fermi GBM detection
  58. Fermi trigger No 705446499: Global MASTER-Net observations report
  59. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  60. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  61. GRB 230510B: MAXI/GSC detection
  62. GRB 230510B: Fermi GBM Final Real-time Localization
  63. GRB 230506B: Fermi GBM detection
  64. GRB 230510A: Swift-XRT refined Analysis
  65. GRB 230506C: Fermi GBM detection
  66. Fermi trigger No 705413051: Global MASTER-Net observations report
  67. GRB 230510A: Fermi GBM Final Real-time Localization
  68. IceCube-230506A: Upper limits from a search for additional neutrino events in IceCube
  69. Fermi-LAT gamma-ray observations of IceCube-230506A
  70. GRB 230506C: Swift-BAT refined analysis
  71. GRB 230506B: Swift-BAT refined analysis
  72. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  73. GRB 230506B: LCOGT Optical Upper Limits
  74. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  75. GRB 230506C: Candidate afterglow observation by D50
  76. IceCube-230506A: IceCube observation of a high-energy neutrino candidate
  77. GRB 230506C: Swift detection of a burst
  78. Swift GRB230506.71: Global MASTER-Net observations report
  79. GRB 230506B: Swift detection of a burst
  80. GRB 230506B: MASTER optical observations
  81. GRB 230506B: Swift detection of a burst
  82. GRB 230506A: Fermi GBM Final Real-time Localization
  83. Fermi trigger No 704837952: Global MASTER-Net observations report
  84. GRB 230427A: Swift-BAT refined analysis
  85. GRB 230503A: Fermi GBM Final Real-time Localization
  86. Konus-Wind detection of GRB 230430A
  87. IceCube-Cascade 230430A: Upper limits from a search for additional neutrino events in IceCube
  88. IPN triangulation of GRB 230430A (short)
  89. GRB 230430B: Fermi GBM Final Localization
  90. GRB 230430A: Fermi GBM observation
  91. GRB 230430A: Fermi GBM Final Real-time Localization
  92. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  93. GRB 230426A: VZLUSAT-2 detection
  94. Fermi trigger No 704365743: Global MASTER-Net observations report
  95. GRB 230428A: Fermi GBM Final Real-time Localization
  96. GRB 230427A : OHP/T193 optical upper limit
  97. GRB 230423A(trigger #1165354): Swift-BAT refined analysis
  98. GRB 230427A: AKO Upper Limit
  99. Swift GRB230427.44: Global MASTER-Net observations report
  100. GRB 230426A: MASTER OT J023135.16-792104.8 optical counterpart discovery

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