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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"

26299 results found.

  1. XRF 030723: confirmation of fading optical counterpart
  2. XRF030723(=H2777): Chandra Observations
  3. Magellan Observations of XRF030723 (=H2777)
  4. GRB030723: Upper limits from historical observations
  5. GRB030725 (=H2779): A Bright GRB Localized by HETE
  6. XRF030723: optical observations
  7. XRF030723, ROTSE-III Early Observations
  8. XRF 030723, optical observations
  9. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  10. Konus-Wind detection of the bursts from SGR1806-20 region
  11. SGR 1806-20, submm observations
  12. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  13. IPN triangulation of GRB030717 (annulus)
  14. RXTE PCA Observations of SGR1806-20 Region
  15. IPN triangulation of GRB030714 (two large error boxes)
  16. IPN triangulation of GRB030715 (two large error boxes)
  17. GRB030329: RTT150 optical observations
  18. GRBlog: Compilation of all GCN Circ. data
  19. IPN detection of renewed activity from SGR1806-20
  20. IPN triangulation of GRB030711 (annulus, =SGR0525-66?)
  21. IPN triangulation of GRB030710 (annulus)
  22. IPN triangulation of GRB030709 (annulus)
  23. GRB030706 triangulation (single large error box)
  24. IPN triangulation of GRB030706 (annulus)
  25. IPN triangulation of GRB030629 (annulus)
  26. GRB030629 triangulation (Konus-Wind -- Helicon annulus)
  27. GRB030329, optical observation in May
  28. IPN triangulation of GRB030626 (two large error boxes)
  29. GRB030329: second XMM-Newton observation
  30. GRB030418: R optical observations
  31. GRB 021206, Radio afterglow candidate
  32. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  33. IPN triangulation of GRB030607 (annulus)
  34. IPN triangulation of GRB030606 (two alternate error boxes)
  35. IPN triangulation of GRB030605B (annulus)
  36. GRB 030528: Optical Observations
  37. IPN triangulation of GRB030605 (annulus)
  38. GRB 030528: tentative NIR counterpart
  39. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  40. IPN triangulation of GRB030601 (annulus)
  41. GRB030329, SPM optical observations
  42. GRB030528: Chandra TOO Planned
  43. GRB030528(=H2724): Revised SXC Localization
  44. GRB 030329: optical observations
  45. GRB 030329/SN 2003dh: Jitter Episode
  46. GRB030528 (H2724): A long GRB localized by HETE
  47. GRB 030528: Optical observations at RIKEN
  48. IPN triangulation of GRB030523B (annulus)
  49. IPN triangulation of GRB030523 (annulus)
  50. GRB 030329: optical photometry at various french observatories
  51. GRB 030329: optical photometry at Belesta observatory (France)
  52. GRB030329, Optical observations
  53. GRB 030329: HST ACS Observations of the Host
  54. GRB030329: XMM-Newton observation
  55. GRB030324: Further Observations of the Candidate Optical Afterglow
  56. IPN triangulation of GRB030519B=H2716 (small error box)
  57. GRB 030418: Second Epoch Optical Observations with Magellan
  58. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  59. IPN triangulation of GRB030519 (annulus)
  60. IPN triangulation of GRB030518C (annulus)
  61. IPN triangulation of GRB030518B (annulus)
  62. IPN triangulation of GRB030518A (annulus)
  63. IPN triangulation of GRB030514 (annulus)
  64. HETE GRB030329, correction to Rc Observations in Loiano
  65. IPN triangulation of GRB030513 (annulus)
  66. IPN triangulation of GRB030509B (annulus)
  67. GRB 030329: Optical limit (contemporaneous imaging)
  68. GRB 030501: final TAROT limits
  69. IPN triangulation of GRB030509 - correction
  70. IPN triangulation of GRB030509 (single error box)
  71. GRB030329: RTT150 optical observations
  72. GRB030329, BVRI photometry
  73. GRB030429, refiend optical brightness
  74. GRB 030329: Optical limit (contemporaneous photography)
  75. GRB 030329: High-Resolution Spectroscopy of the Host
  76. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  77. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  78. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  79. GRB030429: RTT150 optical observations, a possible host galaxy
  80. IPN triangulation of GRB030506 (annulus)
  81. IPN triangulation of GRB030505B (large error box)
  82. IPN triangulation of GRB030505A (annulus)
  83. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  84. GRB030501C triangulation (annulus)
  85. GRB030501 triangulation (correction to GCN 2194)
  86. GRB030329: RTT150 optical observations and upper limit for a host
  87. GRB 030429: Radio Observations
  88. GRB 030429: IR photometry with IRSF/SIRIUS
  89. GRB030501B triangulation (single error box)
  90. GRB030328, optical observation
  91. GRB 030329, BVRI photometry
  92. GRB030429: Optical Observations
  93. GRB 030501: TAROT possible candidate counterpart
  94. IPN triangulation of GRB030501 (IBIS event; annulus)
  95. IPN triangulation of GRB030501B (annulus)
  96. GRB 030429: confirmation of afterglow candidate
  97. GRB030429, possible optical counterpart
  98. GRB030501 localized by INTEGRAL
  99. GRB030425: CrAO optical observation
  100. IPN triangulation of GRB030429 (annulus)

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