May 12, 1998 NOTES from May 9, 1998: The format of the Solar Event Lists was changed to include a standard SEC style header. The format of the event record lines did not change. A list of the current UT day is now available. It is updated every 30 minutes. SOLAR EVENT LISTS This directory contains daily preliminary lists of solar events. The solar event reports received at SEL throughout the day are edited by the duty forecaster to remove incomplete and duplicate reports. This list contains one line for each event reported. The list is updated every 30 minutes throughout the day. The lists for the past 3 days are recreated daily between 0300 and 0330 UT to pick up any late additions or changes. A subset of these lists, called the "energetic" events is included in the daily "Solar Geophysical Activity Summary (SGAS)" report and the "Energetic Events" list in SEL's WEEKLY publication. The sample list below shows typical event reports. The format is fixed, 80 columns wide, with standard headers. The fields are described below. If no events are reported a single line is shown NO EVENT REPORTS. The SEC compiles this list from preliminary data as provided by the contributing stations. Incorrect, missed, and incomplete reports are possible. Your comments and suggestions are welcome. Thank you, Viola Raben vraben@sec.noaa.gov Sample Report ******************************************************************************** :Product: 19980511events.txt :Created: 1998 May 11 2219 UT :Date: 1998 05 11 # Prepared by the U.S. Dept. of Commerce, NOAA, Space Environment Center. # Please send comments and suggestions to sec@sec.noaa.gov # # Missing data: //// # # Edited Events for 1998 May 11 # #Event Begin Max End Obs Q Type Loc/Frq Particulars Reg# #------------------------------------------------------------------------------- 2560 A0146 //// 1225 HOL 3 DSF S17W71 22 B.0A 2580 0402 1452 1732 SVI U RNS 245 200 2540 0434 //// 1732 SVI C RSP 035-08 CTM/2 2520 + 0854 0903 0910 GO9 5 XRA 1-8A B6.9 5.6E-04 2530 + 1037 1047 1110 SVI 3 FLA S22E05 1F ERU 8218 2530 + 1041 1047 1052 GO9 5 XRA 1-8A B9.6 4.8E-04 8218 2550 + 1254 1317 1334 GO9 5 XRA 1-8A B8.4 1.7E-03 2580 1403 1403 1404 SAG G RNS 410 58 2570 + 1856 1900 1907 GO9 5 XRA 1-8A B5.6 3.2E-04 8218 2570 1858 1901 1912 HOL 3 FLA S21E03 SF 8218 2570 1858 1902 1914 RAM 3 FLA S22E02 SF 8218 ******************************************************************************** The first line is the filename. The second line indicates the date/time the list was created. The third line contains the date of the data. Each file (list) contains one UT day of data. Event - This is an arbitrary event number assigned by SEL. It groups several reports into a single event, as determined by the SEL forecaster. + - A plus sign (+) after the event number indicates that more than one report was received for this event, and the forecaster has selected this report to represent those received. Begin, Max, End - The UT Time (UT) of the beginning, maximum, and end of the event as reported by the observing site. "////" indicates a missing time. The UT day of the event's begin time is the UT day of the list. The UT day of the maximum and/or end times may or may not be the same as the begin time. Most solar events are several hours in duration. If the maximum or end time is less than the begin time, then assume the times are for the next UT day. A single letter can proceed a Begin, Max, or End time. A=after, B=before, U=uncertain. For example the begin time A0146 means the event began after 0146. The begin time of an x-ray event is defined as the first minute, in a sequence of 4 minutes, of steep monotonic increase in 0.1-0.8 nm flux. The x-ray event maximum is taken as the minute of the peak x-ray flux. The end time is the time when the flux level decays to a point halfway between the maximum flux and the pre-flare background level. Obs - The reporting observatory. CUL - Culgoora, Australia GO7, GO8, GO9 - GOES 7, 8, or 9 satellites HOL - Holloman AFB, NM, USA LEA - Learmonth, Australia PAL - Palahua, HI, USA RAM - Ramey AFB, PR, USA SAG - Sagamore Hill, PA, USA SVI - San Vito, Italy (See the "Station Lists" directory in the "Welcome" directory for more information.) Q - Quality For radio bursts at fixed and sweep frequencies, and for storms, this shows the quality of the data C = Corrected report G = Good U = Uncertain For optical flares, this shows the quality of observing conditions, from 1 to 5, where: 1 = very poor and 5 = excellent X-ray events have a quality of 5 (meaning excellent). Type - Type of report, (see the Glossary in the "Welcome" directory for definitions). BSL = Bright surge on the limb DSF = Filament disappearance EPL = Eruptive prominence on the limb FIL = Filament FLA = Optical flare observed in H-alpha FOR = Forbush decrease (cosmic ray decrease)) GLE = Ground-level event (cosmic ray increase) LPS = Loop prominence system PCA = Polar cap absorption RBR = Fixed-frequency radio burst RNS = Radio Noise Storm RSP = Sweep-frequency radio burst XRA = X-ray flare Loc/Frq - Location or frequency. Location is in degrees latitude, north or south, and degrees longitude, east or west, from central meridian. The location is the spherical, heliographic coordinates of the solar region, as a distance in degrees from a line extending from the solar equator (heliographic latitude), and distance in degrees from a line extending from the north solar rotational pole to the south solar rotational pole through the center of the solar disk, as viewed from Earth (central meridian) in H-alpha. Frequencies are in Mhz. Particulars - Additional information from the report, chosen on the basis of the report type. XRA: X-ray Class Class x = peak flux in the 0.1 to 0.8 nm range In mks system In cgs system Wm-2 cm-2 s-1 A < x 10-7 x 10-4 B 10-7 <= x 10-6 10-4 <= x 10-3 C 10-6 <= x 10-6 10-3 <= x 10-2 M 10-5 <= x 10-6 10-2 <= x 10-1 X 10-4 <= x 10-1 <= x Integrated flux from start to end, in joules m E-2. FLA: Importance and brightness Importance is the corrected area of the flare in heliospheric square degrees at maximum brightness, observed in the H-alpha line (656.3 nm). S - Subflare (area < or =2.0 square degrees). 1 - Importance 1 ( 2.1 <= area <= 5.1 square degrees) 2 - Importance 2 ( 5.2 <= area <= 12.4 square degrees) 3 - Importance 3 (12.5 <= area <= 24.7 square degrees) 4 - Importance 4 ( area >= 24.8 square degrees) Brightness is the relative maximum brightness of flare in H-alpha. F - faint N - normal B - brilliant Flare Characteristics VWL = Visible in white light UMB = Greater than or equal to 20 percent umbral coverage PRB = Parallel ribbon LPS = Associated Loop Prominence (LPS) YSR = Y-shaped ribbon ERU = Several eruptive centers BPT = One or more brilliant points HSS = Associated high speed dark or bright surge DSF = Flare followed the disappearance of a solar filament in the same region BLU = H-alpha emission greater in the blue wing than in the red wing RBR: The peak value above pre-burst background of associated radio bursts at frequencies 245, 410, 610, 1415, 2695, 4995, 8800 and 15400 MHz: 1 flux unit = 10-22 Wm-2 Hz-1 RSP: The intensity is a relative scale from 1 (low) to 3 (high) of any sweep radio event associated with the energetic event, as follows Type II: Slow drift burst Type III: Fast drift burst Type IV: Broadband smooth continuum burst Type V: Brief continuum burst, generally associated with Type III bursts Type CTM: Broadband, long-lived, dekametric continuum Reg# - The SEL-assigned solar region number. The daily SEL Solar Region Summary report contains detailed information about solar regions.