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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.

Advanced Search Examples (click to copy):

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

42587 results found.

  1. XRF 030723: VLT spectra
  2. Magellan Observations of XRF030723 (=H2777)
  3. GRB030723: Upper limits from historical observations
  4. GRB030725, possible optical transient
  5. XRF030723: Palomar observations and proposed counterpart
  6. GRB030725 (=H2779): A Bright GRB Localized by HETE
  7. XRF030723: optical observations
  8. XRF030723 (= H2777): Chandra Observations Scheduled
  9. XRF030723, BVRcIc field photometry correction
  10. XRF030723, ROTSE-III Early Observations
  11. XRF030723, BVRcIc field photometry
  12. XRF030723, optical observations
  13. XRF 030723, optical observations
  14. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  15. GRB030723, optical observations
  16. Konus-Wind detection of the bursts from SGR1806-20 region
  17. IBAS GRB Alerts 969 970
  18. SGR 1806-20, submm observations
  19. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  20. IPN triangulation of GRB030717 (annulus)
  21. RXTE PCA Observations of SGR1806-20 Region
  22. 030716 NOT a GRB
  23. IPN triangulation of GRB030714 (two large error boxes)
  24. IPN triangulation of GRB030715 (two large error boxes)
  25. GRB030329: RTT150 optical observations
  26. GRBlog: Compilation of all GCN Circ. data
  27. IPN detection of renewed activity from SGR1806-20
  28. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  29. IPN triangulation of GRB030710 (annulus)
  30. IPN triangulation of GRB030709 (annulus)
  31. GRB030706 triangulation (single large error box)
  32. IPN triangulation of GRB030706 (annulus)
  33. IPN triangulation of GRB030629 (annulus)
  34. GRB030629 triangulation (Konus-Wind -- Helicon annulus)
  35. 030629 NOT a real GRB
  36. GRB030329, optical observation in May
  37. IPN triangulation of GRB030626 (single large error box)
  38. IPN triangulation of GRB030626 (two large error boxes)
  39. GRB030329: second XMM-Newton observation
  40. GRB030418: R optical observations
  41. HETE detection of burst from SGR1806-20
  42. GRB030329 -- RATAN-600 data in April-May
  43. Final IPN error ellipse for GRB021206 (the polarized GRB)
  44. GRB 021206, Radio afterglow candidate
  45. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  46. IPN triangulation of GRB030607 (annulus)
  47. IPN triangulation of GRB030606 (two alternate error boxes)
  48. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  49. IPN triangulation of GRB030605B (annulus)
  50. GRB 030528: Optical Observations
  51. IPN triangulation of GRB030605 (annulus)
  52. GRB 030528: tentative NIR counterpart
  53. GRB 030528, radio observations
  54. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  55. GRB030329, further radio observations at GMRT
  56. GRB030528, BVRI field photometry
  57. IPN triangulation of GRB030601 (annulus)
  58. GRB030329, SPM optical observations
  59. GRB030528: Chandra TOO Planned
  60. GRB 030519B: optical observations.
  61. GRB030528(=H2724): Revised SXC Localization
  62. GRB 030329: optical observations
  63. GRB 030329/SN 2003dh: Jitter Episode
  64. GRB 030528, Teramo optical observation
  65. GRB 030528 Bisei optical observation
  66. GRB030528 (H2724): A long GRB localized by HETE
  67. GRB 030329: Correction to GCN 2254
  68. GRB 030329: Optical Observations
  69. GRB 030528: Optical observations at RIKEN
  70. GRB 030528 (=H2724) Kyoto optical observation
  71. IPN triangulation of GRB030523B (annulus)
  72. GRB 030416: Optical Observations
  73. GRB 030329: Planned XMM-Newton Observation
  74. IPN triangulation of GRB030523 (annulus)
  75. GRB 030329: optical photometry at various french observatories
  76. GRB 030329: optical photometry at Belesta observatory (France)
  77. GRB030329, Optical observations
  78. GRB 030329: HST ACS Observations of the Host
  79. GRB 030329 Optical Observations
  80. GRB030329: XMM-Newton observation
  81. GRB 021004: HST observations
  82. GRB030324: Further Observations of the Candidate Optical Afterglow
  83. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  84. IPN triangulation of GRB030519B=H2716 (small error box)
  85. GRB 030418: Second Epoch Optical Observations with Magellan
  86. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  87. IPN triangulation of GRB030519 (annulus)
  88. IPN triangulation of GRB030518C (annulus)
  89. IPN triangulation of GRB030518B (annulus)
  90. IPN triangulation of GRB030518A (annulus)
  91. IPN triangulation of GRB030514 (annulus)
  92. HETE GRB030329, correction to Rc Observations in Loiano
  93. IPN triangulation of GRB030513 (annulus)
  94. IPN triangulation of GRB030509B (annulus)
  95. GRB 030329: Optical limit (contemporaneous imaging)
  96. GRB 030501: final TAROT limits
  97. IPN triangulation of GRB030509 (small errror box)
  98. IPN triangulation of GRB030509 (single error box)
  99. GRB030329: RTT150 optical observations
  100. GRB030329, BVRI photometry

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