! File: 4947C.PROP ! Database: PEPDB ! Date: 23-FEB-1994:11:52:28 coverpage: title_1: HELIUM ABUNDANCE IN JOVIAN PLANET UPPER ATMOSPHERES - CYC2HIGH sci_cat: SOLAR SYSTEM proposal_for: GTO/HSP cont_id: 1082 pi_fname: ROBERT pi_mi: C. pi_lname: BLESS pi_inst: WISCONSIN, UNIVERSITY OF pi_country: USA pi_phone: 608-262-1715 keywords_1: JOVIAN PLANETS, OCCULTATIONS, UPPER ATMOSPHERES, keywords_2: HELIUM ABUNDANCES hours_pri: 10.28 num_pri: 3 hsp: Y time_crit: Y ! end of coverpage abstract: line_1: The large masses of the Jovian planets make it line_2: likely that they have retained their primordial line_3: abundance of material accreted from the solar line_4: nebula. The helium abundance in the upper line_5: atmospheres of these planets reflects the primordial line_6: abundance and the structural evolution of the line_7: planet. We propose to determine the Helium fraction line_8: in the upper atmosphere of each Jovian planet by line_9: measuring the ratio of the refractivities of its line_10: atmosphere for two wavelengths during stellar line_11: occultations. Revision History: Updated for line_12: cycle 2 submission--asb, 4/24/92.; cycle 2 updates, line_13: ASB 1/24/93; ! ! end of abstract general_form_proposers: lname: ROBINSON fname: EDWARD mi: L. inst: TEXAS, UNIVERSITY OF country: USA ! lname: BLESS fname: ROBERT mi: C. inst: WISCONSIN, UNIVERSITY OF country: USA ! lname: VAN CITTERS fname: G. mi: W. inst: NATIONAL SCIENCE FOUNDATION country: USA ! lname: DOLAN fname: JOSEPH mi: F. inst: NASA, GODDARD SPACE FLIGHT CENTER country: USA ! lname: WHITE fname: RICHARD mi: L. inst: SPACE TELESCOPE SCIENCE INSTITUTE country: USA ! lname: ELLIOT fname: JAMES mi: L. inst: MASSACHUSETTS INSTITUTE OF TECHNOLOGY country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We plan to use the ST orbit parameters and the line_2: ephemerides of the Jovian planets to identify those line_3: occultations of sufficient signal-to-noise ratio to line_4: achieve the goals outlined in Section 2. The line_5: observation sequence is as follows: 3) Acquire line_6: occultation candidate using onboard acquisition line_7: mode. 4) Scan along the track that the star will line_8: follow relative to the planet in order to determine line_9: the planetary contribution to the background. 5) line_10: Start continous series of 10ms integrations 10 line_11: arcseconds prior to the predicted immersion time line_12: (for Jupiter). The occultation observation will line_13: require simple tracking on the star before line_14: atmosphere immersion, complex tracking on the line_15: stellar image as it moves along the planetary limb, line_16: and simple tracking after atmosphere emersion. This line_17: sequence of integrations must be continuous. 6) line_18: Scan along the track that the star will follow line_19: relative to the planet For some occultations to be line_20: observed in the far UV, prior multi-filter ! question: 4 section: 1 line_1: We can achieve a much better signal-to-noise ratio line_2: for determining the helium abundance from these line_3: occultations than would be possible from the ground line_4: for the following reasons: (i) the lower level of line_5: background scattered light seen by the ST; (ii) our line_6: ability to reject background light by employing line_7: small focal plane apertures; (iii) the absence of line_8: scintillation noise, which has strong components at line_9: frequencies comparable to the occultation timescale; line_10: and (iv) the much greater span of wavelengths that line_11: can be covered--well into the UV for occultations of line_12: stars of early spectral type. ! question: 5 section: 1 line_1: Aquisition of the object near the planet may be difficult. line_2: Tracking the occulted star in some cases will require a real line_3: time update, due to its complicated path caused by refraction line_4: in the occulting planet's atmosphere and the uncertainties in line_5: predicting the ST orbit. ! question: 6 section: 1 line_1: A prior scan of the path the star will take through line_2: the planetary atmosphere is needed to map the line_3: scattered light field (necessary for the data line_4: reduction). Once the star is in the beamsplitter line_5: aperture and is being occulted by the planet, the line_6: integration sequence must be uninterrupted as the line_7: data are time-critical. ! question: 7 section: 1 line_1: Data will be reduced and analyzed at MIT with the line_2: DEC 5000 belonging to the planetary astronomy line_3: group. ! question: 10 section: 1 line_1: Data reduction and analysis will be supported on line_2: computer facilities at MIT. ! question: 13 section: 1 line_1: The helium abundances in the upper atmospheres of line_2: the Jovian Planets can be obtained with the HSP or line_3: FOS by measuring the refractivities of the line_4: atmospheres at two different wavelengths during line_5: stellar occultations. The helium abundance reflects line_6: the primordial abundance and the structural line_7: evolution of the planet. ! !end of general form text general_form_address: lname: BLESS fname: ROBERT mi: C. category: PI inst: UNIVERSITY OF WISCONSIN addr_1: DEPARTMENT OF ASTRONOMY city: MADISON state: WI zip: 53706 country: USA ! lname: ELLIOT fname: JAMES mi: L. category: CON inst: MASSACHUSETTS INSTITUTE OF TECHNOLOGY addr_1: BLDG. 54-422 city: CAMBRIDGE state: MA zip: 02139 country: USA phone: 617-253-6308 telex: 921473 MIT CAM ! ! end of general_form_address records fixed_targets: targnum: 10 name_1: U115 name_2: GSC6309-00779 descr_1: STAR TO BE OCCULTED BY URANUS. descr_2: CLOSE APPROACH AT 27-JUL-93:21:43 pos_1: PLATE-ID = 068E, pos_2: RA = 19H 25M 29.723S +/- 0.08", pos_3: DEC = -22D 28' 26.15" +/- 0.04", equinox: J2000 acqpr_1: BKG comment_1: SOLAR ELONG 165D fluxnum_1: 1 fluxval_1: V = 10.4 +/- 0.5 ! targnum: 11 name_1: U115-OFFSET name_2: STAR-1926-2229 descr_1: OFFSET TARGET FOR U115 pos_1: RA = 19H 25M 31.691S +/- 0.02", pos_2: DEC = -22D 29' 15.23" +/- 0.08", equinox: J2000 comment_1: STAR POSITION WILL BE UPDATED comment_2: BETWEEN 1.5 AND 4 MONTHS BEFORE comment_3: OCCULTATION DATE. comment_4: CONTACT: AMANDA S. BOSH, MIT fluxnum_1: 1 fluxval_1: V = 13.9 +/- 0.1 ! targnum: 12 name_1: U122 name_2: GSC6324-01532 descr_1: STAR TO BE OCCULTED BY URANUS. descr_2: CLOSE APPROACH AT 15-MAR-94:16:13 pos_1: PLATE-ID = 04O8, pos_2: RA = 19H 50M 26.872S +/- 0.01", pos_3: DEC = -21D 29' 54.77" +/- 0.02", equinox: J2000 acqpr_1: BKG comment_1: SOLAR ELONG 59D fluxnum_1: 1 fluxval_1: V = 11.7 +/- 0.5 ! targnum: 13 name_1: U122-OFFSET name_2: GSC6324-00857 descr_1: OFFSET TARGET FOR U122 pos_1: PLATE-ID = 04O8, pos_2: RA = 19H 50M 30.122S +/- 0.01", pos_3: DEC = -21D 29' 50.26" +/- 0.02", equinox: J2000 fluxnum_1: 1 fluxval_1: V = 13.0 +/- 0.1 ! targnum: 14 name_1: N66 name_2: GSC6309-02511 descr_1: STAR TO BE OCCULTED BY NEPTUNE. descr_2: CLOSE APPROACH AT 18-JUL-93:12:21 pos_1: PLATE-ID = 068E, pos_2: RA = 19H 24M 44.268S +/- 0.02", pos_3: DEC = -21D 19' 15.57" +/- 0.06", equinox: J2000 acqpr_1: BKG comment_1: SOLAR ELONG 174D fluxnum_1: 1 fluxval_1: V = 12.7 +/- 0.5 ! targnum: 15 name_1: N66-OFFSET name_2: STAR-1925-2119 descr_1: OFFSET TARGET FOR N66 pos_1: RA = 19H 24M 42.388S +/- 0.04", pos_2: DEC = -21D 19' 08.79" +/- 0.06", equinox: J2000 fluxnum_1: 1 fluxval_1: B = 15.9 +/- 0.2 ! ! end of fixed targets solar_system_targets: targnum: 18 name_1: U115-BACKGROUND descr_1: OFFSET URANUS lev1_1: STD = URANUS lev2_1: TYPE = POS_ANGLE, lev2_2: RAD = 5.75, lev2_3: ANG = 90.0, lev2_4: REF = NORTH comment_1: FOR USE IN A SCAN OF comment_2: BACKGROUND LEVELS ALONG comment_3: THE PATH OF THE OCCULTED STAR ! targnum: 19 name_1: U122-BACKGROUND descr_1: OFFSET URANUS lev1_1: STD = URANUS lev2_1: TYPE = POS_ANGLE, lev2_2: RAD = 5.24, lev2_3: ANG = 84.5, lev2_4: REF = NORTH comment_1: FOR USE IN A SCAN OF comment_2: BACKGROUND LEVELS ALONG comment_3: THE PATH OF THE OCCULTED STAR ! targnum: 20 name_1: N66-BACKGROUND descr_1: OFFSET NEPTUNE lev1_1: STD = NEPTUNE lev2_1: TYPE = POS_ANGLE, lev2_2: RAD = 5.45, lev2_3: ANG = 85.5, lev2_4: REF = NORTH comment_1: FOR USE IN A SCAN OF comment_2: BACKGROUND LEVELS ALONG comment_3: THE PATH OF THE OCCULTED STAR ! targnum: 22 name_1: URANUS-CENTER descr_1: PLANET URANUS lev1_1: STD = URANUS, ACQ = 0.1 comment_1: ACQUISITION TARGET FOR comment_2: BACKGROUND SCANS fluxnum_1: 1 fluxval_1: SURF(V) = 8.2 +/- 0.5 ! targnum: 23 name_1: NEPTUNE-CENTER descr_1: PLANET NEPTUNE lev1_1: STD = NEPTUNE, ACQ = 0.1 comment_1: ACQUISITION TARGET FOR comment_2: BACKGROUND SCANS fluxnum_1: 1 fluxval_1: V = 7.8 +/- 0.5 ! ! end of solar system targets ! No generic target records found exposure_logsheet: linenum: 4.000 sequence_1: DEFINE sequence_2: ONBRD-ACQ targname: # config: HSP/VIS opmode: ACQ num_exp: 1 time_per_exp: 1S fluxnum_1: 1 priority: 1 ! linenum: 6.000 sequence_1: DEFINE sequence_2: BACK-SCAN targname: # config: HSP/PMT/VIS opmode: SPLIT aperture: 1.0 sp_element: F750W/F320N num_exp: 1 time_per_exp: 1S fluxnum_1: 1 priority: 1 param_1: # req_1: SPATIAL SCAN; ! linenum: 7.000 sequence_1: DEFINE sequence_2: RING-OCC targname: # config: HSP/PMT/VIS opmode: SPLIT aperture: 1.0 sp_element: F750W/F320N num_exp: 1 time_per_exp: 1M fluxnum_1: 1 priority: 1 param_1: # ! linenum: 7.500 sequence_1: DEFINE sequence_2: RING-OCC targname: ^ config: S/C opmode: DATA aperture: NONE num_exp: 1 time_per_exp: ^ priority: 1 param_1: FORMAT=FN, req_1: PAR WITH 7.0; comment_1: CAPTURE FGS TLM DURING OCCULTATION. ! linenum: 10.000 sequence_1: USE sequence_2: ONBRD-ACQ targname: URANUS-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 10.01 - 10.05; req_2: SEQ 10.00 - 10.01 NO GAP; ! linenum: 10.010 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 10.01 - 10.05; req_2: GROUP 10.01 - 10.09 WITHIN 9H; req_3: CYCLE 2/10.00 - 10.30; ! linenum: 10.030 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 10.050 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 10.090 sequence_1: USE sequence_2: ONBRD-ACQ targname: U115-OFFSET time_per_exp: X90 req_1: ONBOARD ACQ FOR 10.10; req_2: SEQ 10.09 - 10.10 NO GAP; req_3: PCS MODE F / 10.09 - 10.10; comment_1: USE FINE LOCK FOR OBSERVATION IF comment_2: BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 10.100 sequence_1: USE sequence_2: RING-OCC targname: U115 time_per_exp: X95 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: AT 27-JUL-93:20:56 +/- 1M; req_2: CRIT OBS; comment_1: END EXPOSURE AT 27-JUL-93:22:30. ! linenum: 10.250 sequence_1: USE sequence_2: ONBRD-ACQ targname: URANUS-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 10.260 - 10.300; ! linenum: 10.260 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 10.26 - 10.30; req_2: GROUP 10.10 - 10.30 WITHIN 9H; ! linenum: 10.280 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 10.300 sequence_1: USE sequence_2: BACK-SCAN targname: U115-BACKGROUND time_per_exp: X147 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 11.000 sequence_1: USE sequence_2: ONBRD-ACQ targname: URANUS-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 11.01 - 11.05; req_2: SEQ 11.00 - 11.01 NO GAP; ! linenum: 11.010 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 11.01 - 11.05; req_2: GROUP 11.01 - 11.09 WITHIN 9H; req_3: CYCLE 2/11.00 - 11.30; ! linenum: 11.030 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 11.050 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 11.090 sequence_1: USE sequence_2: ONBRD-ACQ targname: U122-OFFSET time_per_exp: X30 req_1: ONBOARD ACQ FOR 11.10; req_2: SEQ 11.09 - 11.10 NO GAP; req_3: PCS MODE F / 11.09 - 11.10; comment_1: USE FINE LOCK FOR OBSERVATION IF comment_2: BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 11.100 sequence_1: USE sequence_2: RING-OCC targname: U122 time_per_exp: X95 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: AT 15-MAR-94:15:26 +/- 1M; req_2: CRIT OBS; comment_1: END EXPOSURE AT 15-MAR-94:17:00. ! linenum: 11.250 sequence_1: USE sequence_2: ONBRD-ACQ targname: URANUS-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 11.260 - 11.300; ! linenum: 11.260 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 11.26 - 11.30; req_2: GROUP 11.10 - 11.30 WITHIN 9H; ! linenum: 11.280 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 11.300 sequence_1: USE sequence_2: BACK-SCAN targname: U122-BACKGROUND time_per_exp: X140 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 12.000 sequence_1: USE sequence_2: ONBRD-ACQ targname: NEPTUNE-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 12.01 - 12.05; req_2: SEQ 12.00 - 12.01 NO GAP; ! linenum: 12.010 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 12.01 - 12.05; req_2: GROUP 12.01 - 12.09 WITHIN 9H; req_3: CYCLE 2/12.00 - 12.30; ! linenum: 12.030 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 12.050 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 12.090 sequence_1: USE sequence_2: ONBRD-ACQ targname: N66-OFFSET time_per_exp: X180 req_1: ONBOARD ACQ FOR 12.10; req_2: SEQ 12.09 - 12.10 NO GAP; req_3: PCS MODE F / 12.09 - 12.10; comment_1: USE FINE LOCK FOR OBSERVATION IF comment_2: BRIGHT ENOUGH GUIDE STARS CAN BE comment_3: FOUND. IF NOT, COARSE TRACK IS comment_4: ACCEPTABLE. ! linenum: 12.100 sequence_1: USE sequence_2: RING-OCC targname: N66 time_per_exp: X110 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: AT 18-JUL-93:11:31 +/- 1M; req_2: CRIT OBS; comment_1: END EXPOSURE AT 18-JUL-93:13:20. ! linenum: 12.250 sequence_1: USE sequence_2: ONBRD-ACQ targname: NEPTUNE-CENTER time_per_exp: X1 req_1: ONBOARD ACQ FOR 12.260 - 12.300; ! linenum: 12.260 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, req_1: SEQ 12.26 - 12.30; req_2: GROUP 12.10 - 12.30 WITHIN 9H; ! linenum: 12.280 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! linenum: 12.300 sequence_1: USE sequence_2: BACK-SCAN targname: N66-BACKGROUND time_per_exp: X99 param_1: SAMPLE-TIME = 0.01, param_2: DATA-FORMAT = ALL, param_3: PMT-ANALOG = 1000, param_4: VIS-ANALOG = 100, ! ! end of exposure logsheet scan_data: line_list: 10.01, 10.05, 10.26, 10.30 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 0.0000 scan_length: 33.5000 sides_angle: 90.0000 number_lines: 1 scan_rate: 0.0750 first_line_pa: 261.8000 scan_frame: CEL len_offset: 0. wid_offset: 0 ! line_list: 10.03, 10.28 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 1.0000 scan_length: 33.5000 sides_angle: 90.0000 number_lines: 3 scan_rate: 0.0750 first_line_pa: 261.8000 scan_frame: CEL len_offset: 0. wid_offset: 0.5 ! line_list: 11.01, 11.05, 11.26, 11.30 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 0.0000 scan_length: 33.0000 sides_angle: 90.0000 number_lines: 1 scan_rate: 0.0750 first_line_pa: 260.0000 scan_frame: CEL len_offset: 0. wid_offset: 0 ! line_list: 11.03, 11.28 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 1.0000 scan_length: 33.0000 sides_angle: 90.0000 number_lines: 3 scan_rate: 0.0750 first_line_pa: 260.0000 scan_frame: CEL len_offset: 0. wid_offset: 0.5 ! line_list: 12.01, 12.05, 12.26, 12.30 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 0.0000 scan_length: 29.9000 sides_angle: 90.0000 number_lines: 1 scan_rate: 0.0750 first_line_pa: 261.2000 scan_frame: CEL len_offset: 0. wid_offset: 0 ! line_list: 12.03, 12.28 fgs_scan: cont_dwell: C dwell_pnts: 0 dwell_secs: 0.00 scan_width: 1.0000 scan_length: 29.9000 sides_angle: 90.0000 number_lines: 3 scan_rate: 0.0750 first_line_pa: 261.2000 scan_frame: CEL len_offset: 0. wid_offset: 0.5 ! ! end of scan data