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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"

25026 results found.

  1. XRF030723, ROTSE-III Early Observations
  2. XRF030723, BVRcIc field photometry
  3. XRF 030723, optical observations
  4. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  5. Konus-Wind detection of the bursts from SGR1806-20 region
  6. SGR 1806-20, submm observations
  7. RXTE PCA Observations of SGR1806-20 Region
  8. IPN triangulation of GRB030714 (two large error boxes)
  9. IPN triangulation of GRB030715 (two large error boxes)
  10. GRB030706 triangulation (single large error box)
  11. GRB030329, optical observation in May
  12. IPN triangulation of GRB030626 (single large error box)
  13. IPN triangulation of GRB030626 (two large error boxes)
  14. GRB030329: second XMM-Newton observation
  15. GRB030329 -- RATAN-600 data in April-May
  16. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  17. IPN triangulation of GRB030606 (two alternate error boxes)
  18. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  19. GRB 030528: tentative NIR counterpart
  20. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  21. GRB030528, BVRI field photometry
  22. GRB030329, SPM optical observations
  23. GRB030528: Chandra TOO Planned
  24. GRB030528(=H2724): Revised SXC Localization
  25. GRB 030528 Bisei optical observation
  26. GRB030528 (H2724): A long GRB localized by HETE
  27. GRB 030329: Correction to GCN 2254
  28. GRB 030329: Optical Observations
  29. GRB 030528 (=H2724) Kyoto optical observation
  30. GRB 030416: Optical Observations
  31. GRB 030329 Optical Observations
  32. GRB030329: XMM-Newton observation
  33. GRB 021004: HST observations
  34. GRB030324: Further Observations of the Candidate Optical Afterglow
  35. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  36. IPN triangulation of GRB030519B=H2716 (small error box)
  37. HETE GRB030329, correction to Rc Observations in Loiano
  38. GRB 030329: Optical limit (contemporaneous imaging)
  39. IPN triangulation of GRB030509 (small errror box)
  40. GRB030329, BVRI photometry
  41. GRB030429, refiend optical brightness
  42. GRB 030329: Optical limit (contemporaneous photography)
  43. GRB030418, BVRcIc field photometry
  44. GRB030429, BVRcIc field photometry
  45. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  46. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  47. GRB030329: RTT150 optical observations and upper limit for a host
  48. GRB030501, optical observation
  49. GRB030501 triangulation (correction to GCN 2194)
  50. GRB030329: RTT150 optical observations and upper limit for a host
  51. GRB 030429: redshift from VLT spectroscopy
  52. GRB030501B triangulation (single error box)
  53. GRB 030329, BVRI photometry
  54. GRB030429: Optical Observations
  55. GRB030501: TAROT candidate afterglow present in archival images
  56. GRB 030429: confirmation of afterglow candidate
  57. GRB 030329 Oprical observations in Rozhen observatory
  58. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  59. IPN triangulation of GRB030425 (single error box)
  60. GRB 030329, the review of the sky area in plate archive (1950-1998)
  61. GRB 030329: optical spectropolarimetry at VLT
  62. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  63. GRB030329: optical polarization
  64. IPN triangulation of GRB030422 (two large error boxes)
  65. GRB030329, optical observation
  66. MASTER:optical observations GRB030418
  67. MASTER:optical observations probable GRB030414
  68. GRB030418: Kiso near infrared observations
  69. GRB 030418: Optical afterglow
  70. OT GRB 030329: early UBVRcIc spectral evolution
  71. OT GRB 030329: early spectrum
  72. IPN triangulation of GRB030414 (small error box)
  73. IPN triangulation of GRB030413 (small error box)
  74. Superluminal motion in GRB 030329 (Correction)
  75. Superluminal motion in GRB 030329
  76. GRB030329, optical position
  77. IPN triangulation of GRB030406 (small error box)
  78. IPN triangulation of GRB050403 (small error box)
  79. GRB 030329: BVRI photometry at Asiago
  80. GRB 030329: VLT V-band photometry
  81. Kiso observation of the GRB030329 at April 6
  82. GRB 030329, color evolution
  83. GRB030328, UBVRcIc field photometry
  84. GRB 030329 Optical observations
  85. GRB030329: Kiso B and R band observations
  86. GRB030328: R upper limit after 6 hours by MASTER
  87. SDSS 0.5m PT observations of GRB030329 (correction)
  88. SDSS 0.5m PT observations of GRB030329
  89. GRB030329: final R-band light curve by MASTER
  90. GRB030329, optical observation
  91. GRB030329, new UBVRcIc field photometry
  92. GRB 030329, light curve and SN prediction
  93. GRB 030329, BRI photometry
  94. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  95. GRB030329: Optical observations at Teramo
  96. GRB 030329: Radio observations at GMRT
  97. Further AAVSO V,B,R observations of GRB030329
  98. GRB 030329: Additional Mt. Laguna Optical Observations
  99. GRB 030329: Observations with ANDICAM
  100. GRB030329: further optical photometry and evidence for a light curve discontinuity

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