SOLAR ORBITER
SWA
Proton-Alpha Analyzer (PAS)
Main Reference Document (PAS Bible)
V.3.0

Andrey Fedorov

andrei.fedorov@irap.omp.eu

08/11/2022

1 The scope of this document and important references

The present document reflects the current state of PAS in flight. It shows the principal summary of all instrument design and features. Usually one needs to read this document only to understand the instrument design, performance and control.

The main important references:

IRAP PAS flight data, control, documents, etc : IRAP Solar Orbiter page (if you need a login and password, ask us)
IRAP PAS operation_and_data_log: PAS operation/data summary
Where is Solar Orbiter: Where is Solar Orbiter

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2 General principles

The Solar Orbiter spacecraft and location of the PAS instrument is shown in Figure 1. There you can see also the PAS and the spacecraft axis definitions, and angular bin relative locations.

image: 0_home_fedorov_SOLARORB_PAS_THE_BIBLE_DATA_DESCRIPTIONS_PAS_frame_SC_frame_20201013.jpg

Figure 1: SC and instrument bins definitions

The instrument general conception is shown in Figure 2. The main conception principles are:

To protect the instrument from the very strong incidence heat and light flux the instrument aperture is a thin slit. Also the the instrument is protected by its own thermal shield (red in the image).
The internal electrostatic optics ( blue in the image) is positioned to avoid direct impact of the light to the optical surfaces. We assumed the the spacecraft can varies the sun-pointing attitude (due to an attitude control failure) in $\pm 6^{○}$ range.
The electrostatic optics consists of the elevation (top image plane) deflector, choosing the ion direction, and the electrostatic analyzer, filtering the ion energy, followed by the array of detectors.
The detectors array is located along the azimuthal plane (bottom panel of Figure 2) that allows to resolve the azimuthal direction of the detected ions.

image: 1_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_ConceptionBase_8_Nov_2014.jpg

Figure 2: PAS general measurement principles

Azimuthal binning is shown in Figure 3 as a view from -Z spacecraft side.

image: 2_home_fedorov_SOLARORB_PAS_PASDOCS_UNITSPEC_PasAzimuthBinning_29_Sep_2014.png

Figure 3: PAS azimuthal binning

Conception of the elevation binning is in Figure

image: 3_home_fedorov_SOLARORB_PAS_PASDOCS_UNITSPEC_PasElevationBinning_26_Sep_2014.png

Figure 4: PAS elevation beaning and sweeping scheme

General measurement diagram: 10 Sep 2014

image: 4_home_fedorov_SOLARORB_PAS_THE_BIBLE_PAS_Cycle_WaveForm_09_Sep_2014.jpg

Figure 5: Sampling waveform with counters accumulation windows

image: 5_home_fedorov_SOLARORB_PAS_PASDOCS_UNITSPEC_Measur_Princip_10_Sep_2014.png

Figure 6: PAS sampling diagram

2.1 Common View

25 Sep 2014

image: 6_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PAS_Common_View_10_Jun_2014.jpg

Figure 7: PAS 3D transparent view

The photo (STM):

image: 7_home_fedorov_SOLARORB_PAS_LOG_PAS_STM_for_Presentations_27_Aug_2014.jpg

Figure 8: PAS STM photo

2.2 Ion Optics Design

Definitions:

Term	What is it	Unit	Comment
$E$	Particle energy	$e V / Q$
$U_{A N}$	Analyzer voltage	$V$	Always positive
$U_{T O P D}$	Upper Deflector Plate Voltage	$V$	Positive/Negative
$U_{B O T D}$	Bottom Deflector Plate Voltage	$V$	$U_{B O T D} = - U_{T O P D}$
$U_{T P}$	Top Cap Voltage	$V$	Positive/Negative
$Φ$	Incident Elevation (polar) angle	deg	See Figure
$D$	$U_{T O P D} / U_{A N}$
$K$	$E / U_{A N}$		13.2 (HIS calibr)
$T$	$U_{T P} / U_{A N}$

Table 1: Ion optics definitions

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Figures 9, 10 and 11 show all details of PAS ion optics system design.

image: 23_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_I___MAGES_PAS_Ion_Optics_Conception_31_Jan_2013.png

Figure 9: XZ and XY cuts of the PAS ion optics

image: 24_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PAS_collim_spec.png

Figure 10: PAS collimator ZOOM

image: 25_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PAS_Sphera_Scallop.png

Figure 11: PAS spheres scalloping

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2.3 Instrument properties based on ray-tracing and calibration

Results of the PAS last calibrations ( the reference doc: TBD), Date TBD

Esteps = double(18565.0*0.943^findgen(96)) (Sequencer 5.0, 2019)

U_{A N} = E / K = E / 13.2 = 1515.2 \cdot 0.952 7^{i e}

D (Φ) = 1.603 - 0.1816 \cdot Φ - 0.00159 \cdot Φ^{2} = C D_{0} + C D_{1} \cdot Φ + C D_{2} \cdot Φ^{2}

U_{T O P D} = - D \cdot U_{A N}

To control Top Cap the algorithm should be as follows:

image: 8_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_20190321_PAS_FS_D-T_Seq_nodes.jpg

Figure 12: PAS deflector calibration and the sequence nodes

There is a table of values (TO CORRECT!):

	0	1	2	3	4	5
Dr(i)	-3.03	-0.79	1.32	2.37	3.3	4.88
Tr(i)	5.28	2.64	0.66	-2.90	-5.94	-3.96
dTdD(i)	-1.179	-0.938	-3.39	-3.269	1.253

Table 2: Deflectors nodes table (TB corrected)

Define $D (Φ)$
Define $i d$ and $i d + 1$ where $D (Φ)$ is between
Calculate T $T (Φ) = (T_{i d + 1} - T_{i d}) / (D_{i d + 1} - D_{i d}) \cdot (D (Φ) - D_{i d}) + T_{i d} = d T d D_{i d} \cdot (D (Φ) - D_{i d}) + T_{i d}$

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2.4 PAS block-diagram and general configuration.

PAS block diagram V.4.0 form 29 Apr 2014

There are two separated HV and principally independent units: 1) DEFLHV (Analyzer and deflector HV) formally includes all DACs; 2) CEMHV references DACs are formally included into the FPGA board.

image: 9_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PasBlockDiag_V5_31_Jul_2015.jpg

Figure 13: PAS block diagram. Version 4.0, 29 Apr 2014,

3 Design details

This section TO BE COMPLETED.

3.1 Mechanical Design

Ebanol-C coating

The general structure is in Figure 14. Origin: Dheren Dec 2013.

image: 10_home_fedorov_SOLARORB_PAS_LOG_Ebonol_C_structure_17_Dec_2013.jpg

Figure 14: Ebanol-C common structure

3.2 Detectors Board

image: 11_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_CEM_Allocation_req_10_Nov_2014.jpg

Figure 15: PAS CEM polarization

Conception of the resistance and high/low count rate in the azimuthal binning.

0 1 2 3 4 5 6 7 8 9 10

200M | 200M 80M 80M 80M 80M 80M 200M | 200M 200M 200M

|------- Central part ----------|

3.3 HV Optic Board

The spec of the HV profiles for Detector Board and HV Optics board:

image: 12_home_fedorov_SOLARORB_PAS_THE_BIBLE_PAS_FS_HV_profile_example.jpg

Figure 16: Detector board and HVOptic board Profile SPEC

3.4 FPGA

3.4.1 HV control

image: 13_home_fedorov_SOLARORB_PAS_THE_BIBLE_PAS_HV_Control_25_Nov_2014.jpg

Figure 17: HV and amplifiers power diagram

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image: 14_home_fedorov_SOLARORB_PAS_THE_BIBLE_HK_reading_Scheme_24_Nov_2014.jpg

Figure 18: HK reading diagram

The PAS Sequencer performs the HV stepping and data sampling in two schemes: “STATIC scheme” and “DYNAMIC Scheme”. See Figures 19 and 20. At any case each scheme is a sequence of Samplings. Each sampling (or set of samplings) can be configurated using the parameters as shown in Table 3. DPU starts the static scheme by sending “1” to the PAS mailbox, and starts the dynamic scheme by sending “2” to mailbox.

The static scheme is also configurated by parameters “K” and “N”. After start of the static scheme the Sequencer runs N seconds and that stop to the idle for 3 seconds, and then restart the Static Scheme again. This process continues until PAS receives “0” to its mailbox from DPU (stop scheme after N seconds) or '0xFF' (stop immediately). Note the static sampling parameters are defiled by Ne, Se, Nel, Sel, provided by DPU.

The Dynamic scheme needs additional configuration of for the “Full Sampling”, The sequencer performs this “Full Sampling” before each “N” seconds interval. Such sequence: “Full Samplings”, N seconds of N*K samplings are repeating L times and the Sequencer performs the Full Sampling again after the end of a whole L interval. Then, after 3 seconds of idle, the Sequencer starts again the dynamic mode. The Sequencer is updating Se and Sel of normal samplings after each Full Sampling execution.

Name	Parameter	Range	Usage
Ne	Energy steps number	2 ... 96 (evens only)	Individual sampling, S and D
Se	Start energy number	0 ... 94 (evens only)	Individual sampling, S
Nel	Elevation steps number	1 ... 9	Individual sampling, S and D
Sel	Start Elevation	0 ... 8	Individual sampling, S
K	Number of samplings in one sec.	> 0	Individual sampling, S and D
N	Number of seconds of	>0	Static and
	of continuous sampling		Dynamic
L	Number of intervals of N seconds	>0	Dynamic

Table 3: Sampling Configuration

DPU memory contains special tables (Section 6.1 with configurations for different modes (see Section 6.5 and 6.6).

image: 15_home_fedorov_SOLARORB_PAS_THE_BIBLE_PAS_Static_Schema_19_Dec_2014.png

Figure 19: Static Scheme

image: 16_home_fedorov_SOLARORB_PAS_THE_BIBLE_PAS_Peak_Track_Schema_19_Dec_2014.png

Figure 20: Dynamic Window Scheme

image: 17_home_fedorov_SOLARORB_PAS_THE_BIBLE_Elevation_Scan_Disg_14_Dec_2014.png

Figure 21: Elevation scan for the general sampling

image: 18_home_fedorov_SOLARORB_PAS_PASDOCS_UNITSPEC_Energy_Scan_Disg_15_Dec_2014.png

Figure 22: Energy scan for general sampling

image: 19_home_fedorov_SOLARORB_PAS_THE_BIBLE_Energy_Scan_Nel1_15_Dec_2014.png

Figure 23: Energy scan for constant elevation sampling

4.1 Pulse generator for EQM and PFM

#CEM in TC	0	1	2	3	4	5	6	7	8	9	10
CEM EQM	6	7	8	9	10	-	0	1	2	3	4
CEM PFM (EM)	0	1	2	3	4	5	6	7	8	9	10

Table 4: Addressing of the test pulse generator

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4.2 CEM manipulations

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4.2.1 How to set the HV on CEM

The digital command to set the CEM voltage is defined as:

D A C = r o u n d (H V [V] / 1.221)

The character values for the steps are in the table below:

Step, V	50	100	200	500
Decimal	0041	0082	0164	0410
HEX	0x0029	0x0052	0x00A4	0x019A

4.3 All versions of Sequencers and Configuration tables

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Sequencer	Version/ Time	Stepping configuration table	Version/ Time	Usage
PAS_SCI_FM_4_0_Full_Image.hex	4.0	FM_Stepping_Configuration_Table_v2.0.txt	2.0	with PFM at Delivery
	May 2017	Fiche de configuration des parametres du sequenceur FM - v2.0.xlsx	May 2017
	4.1		3.0
PAS_SCI_FM_5_0_Full_Image.hex	5.0	FM_Stepping_Configuration_Table_v4.0.txt	4.0	installed to DPU S/W version 3.9
	2019.04.12	Fiche de configuration des parametres du sequenceur FM - v4.0.xlsx	2019.04.12	in the PAS PFM since Oct 2019
		Fiche de configuration des parametres du sequenceur FS - v4.2.xlsx		Special file with FS offsets
	5.1		4.2

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4.4 Current version installed to DPU-PAS-PFM (20 Nov 2019)

Version	5.0, 2019.04.12	PASDOCS/FPGADPU/FPGA_SEQUENCER/SEQUENCER_5_0/
File to load	PAS_SCI_FM_5_0_Full_Image.hex	HEX
Sequencer Code	PAS_SCI_FM_5_0.txt
Stepping Configuration table	FM_Stepping_Configuration_Table_v4.0.txt	Before the flight, the offsets are 0
Configuration Table as a spreadsheet	PAS_Stepping_Conf_Table_v4_0.xlsx	also .csv
Sequencer Configuration spreadshiit	Fiche de configuration des parametres du sequenceur FM - v4.0.xlsx	Before the flight, the offsets are 0
Code to transfer to TC	FPGA_SEQUENCER/TC_CONVERTER/PAS_config_table_TC.pro

Table 5: FM istalled Sequencer and config.

The Table 6 shows the Energy (Analyzer) sets. These constants are also in the “Sequencer Configuration spreadsheet” (Table 5)

Start Uan, V	1338.7	Configuration table
Analyzer K (Calibration)	13.782	PAS_FS_Calibration**.lyx
Start Energy, eV	18450.5
$E_{i + 1} / E_{i}$	0.943	Configuration table

Table 6: Analyzer and Energy table configuration

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4.5 HV control, HK decoding, and FDIR parameters

All HK decoding coefficients are in PAS_HK_Conversion_all_models_25_Mar_2020.

The DPU FDIR limits are in SWA_PAS_PFM_FDIR_Limits_01_Feb_with_actions_2019.

5 COMMISSIONING special settings

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5.1 Engineering mode table commissioning

The table below (Table 7) correspond to the file FLIGHT/COMMISSIONING/Engineering_Scheme_params_22_Nov_2019.xlsx

Parameter	Real Value	Dec Value	HEX
ANL_MAX	600 V	6292712	0x6004E8
K	0.255436	4285512	0x416448
ANL_TD_RATIO	1.15228	1208253	0x126FBD
ANL_BD_RATIO	1.14495	1200569	0x1251B9
ANL_TC_RATIO	1.14831	1204086	0x125F76
HT_STEPS_DURATION	60 s	60	0x00003C

Table 7: Engineering table for commissioning

6 DPU and CRUISE OPERATIONS

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6.1 DPU registers with default PAS parameters

The default parameters are described in the spreadsheet: SWA_UM_V2_PAS_only

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6.1.1 Normal mode default

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6.1.2 BURST mode defaults

Preface for all parameters: pasConfParam.

Content is in Table 8

Name	Length, bits	value, hex	decimal	comment
DynamicBurst.Channeltron	24	0x000001	1	0 - all, 1 - centrals
				3 - special, no Idle
DynamicBurst.FirstEnergy	24	0x000000	0	Full 3D
DynamicBurst.EnergyNum	24	0x00005C	92	Full 3D
DynamicBurst.FirstElev	24	0x000000	0	Full 3D
DynamicBurst.ElevNum	24	0x000009	9	Full 3D
DynamicBurst.EnerWinSize	24	0x000030	48	Fast Dynamic
DynamicBurst.ElWinSize	24	0x000003	3	Fast Dynamic
DynamicBurst.K	24	0x000004	4	Fast Dynamic
DynamicBurst.N	24	0x000013	19	Duration Fast Sect
DynamicBurst.L	24	0x00000F	15	Number Full3D + Fast Sect

Table 8: Default contents of Burst Mode Register 0x3009

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6.2 DPU - PAS state machine

TO DO a short description

image: 20_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_State_Mashine_flow_14_Nov_2018.jpg

Figure 24: DPU-side PAS state machine

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6.3 MLT level PAS control

In most of case the it is prohibited for us to send directly TCs to DPU-PAS. To avoid errors, during the flight, we have to operate DPU -> PAS by special Mission Timeline (MTL) “Sequences”. The sequence is a set of TCs with corresponding arguments. Some arguments of TCs can be the arguments of the Sequence. The list of the PAS sequences are shown in Table 9.

MOC ID	Procedure Name	File	Version	Duration	Comment
AIAF016A	PAS ON	PAS_MTL_ON_procedure	4.2	100 s	The first part of PAS activation procedure
AIAF060A	PAS Configure	PAS_MLT_Config_procedure	4.0	formula (a)	The second part of PAS activation procedure
AIAF066B	PAS FDIR activate	PAS_MTL_FDIR_ACTIVE_procedure	1.0	34 s	The third part of PAS activation procedure
AIAF068A	PAS Normal Config	PAS_Normal_Mode_Config	1.0	4 s	Normal mode Configuration
AIAF069A	PAS Burst Config	PAS_Burst_Mode_Config	1.0	4 s	Burst mode Configuration
AIAF131A	PAS SnapShot	PAS_SnapShot_Config	1.0	4 s	SnapShot Configuration
AIAF067A	PAS Calibration	PAS_Calibration_procedure	3.1	formula (b)	Calibration of CEM HVs
AIAF130A	PAS Apply CEM HV	PAS_CEM_HV_procedure	4.0	25 s	Apply new CEM HV
AIAF065A	PAS_TTF_Safe	PAS_TTF_Safe_procedure	4.0	290 s	for planned Thruster Firing (TTF)
AIAF066A	PAS_TFF_Recovery	PAS_TTF_Recovery_procedure	4.1	formula (c)	for planned TTF
AIAF006A	PAS OFF	PAS_MLT_OFF_procedure	3.1	240 s	PAS normal OFF MTL procedure

Table 9: PAS MTL sequences

Important information:

At the top of each sequence spreadsheet there is a list of formal parameters (arguments). The position of these parameters in the sequence bode are shown by yellow. The red color shows the individual TC parameters that cannot be modified.
At the bottom of each sequence (if the sequence duration is > 10 seconds) we put the duration of the procedure (yellow) or a duration calculator. We also show the duration in the formulas below:
1. Config_procedure[s] = 715 + 25* <CEM_Nominal_Voltage[V]>/50 + 30
2. Calibration_procedure[s] = 24*<Nsteps of CEM HV> +10 sec; Nsteps_of_CEM_HV = ROUND((STOP_HV - START_HV)/50 + 1.0)
3. TTF_Recovery[s] = 210 + 25* <CEM_Nominal_Voltage[V]>/50 + 30

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6.4 General notes about DPU - PAS communication

It is very important to understand that for some reason DPU can directly process and transmit toward the Solar Orbiter Onboard Computer (OBC) only data of STATIC scheme with N = 1 (i.e. one second data repeating each 3 seconds. Any other type data (STATIC with N > 1, or any type of DYNAMIC scheme) are storied in the rolling memory in DPU. DPU start to transmit the data from the rolling memory toward OBC as soon as the PAS stops generate a fast data flow. For some reason the DPU rolling memory capacity is just 5 minutes.

“Flight” sequencer PAS_SCI_FM_5_0_Full_Image.hex is working with the “COMMISSIONING patch” this patch keeps all CEM HVs always nominal

To activate such a “constant CEM HVs” and correctly activate PAS amplifiers, we use a special procedure described in file “PAS_MLT_Config_procedure_V_4_0_28_May_2020.xlsx”
To understand the HV control conversion factors see PAS_HK_Conversion_all_models_25_Mar_2020.xlsx

; SWA_TC_PAS_WR_MASTER_CTRL_REG ( 1 parameters )

TC, ZIA58863, PIA60343, EQUAL, 0x00000007 # CEMs ON

Wait 5 s

; SWA_TC_PAS_WR_PREAMP_CTRL_REG ( 2 parameters )

TC, ZIA58862, PIA58062, EQUAL, ON # PRE_AMP1 ON

TC, ZIA58862, PIA58063, EQUAL, ON # PRE_AMP2 ON

Wait 5 s

; SWA_TC_PAS_LOAD_STATIC_TABLE ( 7 parameters )

TC, ZIA58876, PIA60700, EQUAL, 0x000000 # All CEMs

TC, ZIA58876, PIA60713, EQUAL, 0x000008 # Se

TC, ZIA58876, PIA60705, EQUAL, 0x000040 # Ne = 64

TC, ZIA58876, PIA60712, EQUAL, 0x000000 # Sel

TC, ZIA58876, PIA60704, EQUAL, 0x000009 # Nel = 9

TC, ZIA58876, PIA60720, EQUAL, 0x000001 # K = 1

TC, ZIA58876, PIA60721, EQUAL, 0x000001 # N = 1

Wait 5 s

; SWA_TC_PAS_WR_MAILBOX_CTRL ( 1 parameters )

TC, ZIA58873, PIA60347, EQUAL, 0x00000001 # Start Static Scheme

Wait 30 s

; SWA_TC_PAS_WR_MAILBOX_CTRL ( 1 parameters )

TC, ZIA58873, PIA60347, EQUAL, 0x000000FF # Abort Sequencer activity

Wait 5 s

Table 10: Activation the amplifiers and CEMs HV before to ramp up CEMs HVs

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6.5 MODES and performance control

There are two modes of PAS: “Normal Mode (NM) and Burst Mode (BM). The performance of these modes is fully controlled by DPU. DPU sends special TC to PAS according to the internal hardly programmed schedule synchronized to the SCET (Spacecraft Elapsed Time). Note that SCET is NOT equal to UTC and slowly moves relatively UTC. Thus the shift between UTC and SCET is different for each new week.

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6.5.1 NORMAL MODE

The Normal Mode diagram is shown in Figure 25. It consists normally of different STATIC scheme samplings (see Section 4 and Figure 19), but every 300 s DPU starts a short DYNAMIC scheme (Section 4 and Figure 20). It is important to understand that DPU controls the NM performance as follows:

Before 100 s (SCET) boundary DPU configures Full Sampling (FS) and starts STATIC scheme with K=1, N=1. PAS performs one FS 0.5 s later 100 s boundary.
Then DPU recalculates the Se and Sel for Normal Sampling (S) , configure it, and starts STATIC scheme execution with N = 1
Before 300 s (SCET) boundary DPU stops Normal Sampling, configure the DYNAMIC scheme with N=7 and L=1, and starts a DYNAMIC scheme to center it around the 300s boundary

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image: 21_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_I___S_Nrmal_mode_Snap_300s_V_2_3_21_Nov_2016_HR.jpg

Figure 25: Normal Mode diagram

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6.5.2 BURST MODE

A BM example diagram is shown in Figure 26. Such BM configuration has been used during 2021 - 2022. The BM is a realization of the Dynamic Scheme with fixed parametres (see Table 11). These parameters can be modified via a special dedicated procedure only. Other Dynamics Scheme parameters can be easily modified run-time (see Table xxx in Section 6.6). Note that for the memory protection reason DPU stops BM execution at 296 second after the start, and loose the last Full Sampling (FS) of this NM.

Parameter	Value	Comment
N	19	length in seconds of fast samplings
L	16	number of fast intervals
		separated by full sampling

Table 11: Fixed BM parameters

image: 22_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PAS_BM_layout_20220217.jpg

Figure 26: Burst Mode (BM)

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6.6 PAS Configuration

At the beginning of each Short Time Planning (STP, one week usually) we make, reconfiguration of the PAS configuration table storied in the DPU memory. The same we have to do after each PAS OFF. The procedure is looking as shown in Table 12.

00:04	AIAF068A	Configure_PAS_NM	0x00, 0x14, 0x40, 0x00, 0x09, 0x01
00:04	AIAF131A	Configure_PAS_snapshot	0x00, 0x04, 0x5A, 0x00, 0x09, 0x24, 0x05, 0x04
00:04	AIAF069A	Configure_PAS_BM	0x00, 0x04, 0x5A, 0x00, 0x09, 0x24, 0x05, 0x04

Table 12: An example of the PAS configuration in a STP planning

The explication of the parameters are given in the PAS_Modes_Flight spreadsheet. This spreadsheet shall be used to keep the current configuration and to check new STP plans.

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6.7 Special notes about STATIC mode

If PAS has to be in the STATIC mode, every time after PAS recovery or ON, we have to start NM, stop NM and Start STATIC. We need this to correctly configure PAS internal tables and set the energy and elevation windows to the correct position relatively solar wind peak. The procedure looks like in Table 13.

00:02	AIAF061A	Start_PAS_science
01:50	AIAF063A	Stop_PAS_science
00:20	AIAF061B	Start_PAS_static_mode_science

Table 13: Start STATIC mode after PAS recovery or ON. The time intervals may vary.

Every 0:00, 6:00, 18:00 we do the STATIC mode energy and elevation windows adjusting using the procedure shown in Table 14.

	AIAF133A	Abort_the_PAS_sequencer
00T00:00:01	AIAF063A	Stop_PAS_science
00T00:00:09	AIAF061A	Start_PAS_science
00T00:01:40	AIAF063A	Stop_PAS_science
00T00:00:20	AIAF061B	Start_PAS_static_mode_science

Table 14: Adjust STATIC mode. The time intervals may vary

In both cases the rools are as follows:

We have to start NM (AIAF061A) AFTER the 300 s SCET boundary, in the time interval [ 20 : 90] or [120 : 190] seconds offset after the 300 s SCET boundary
We have to stop NM 100s (AIAF063A) (+/- 5 s) after the start.
We can restart STATIC in 20 s after the NM stop

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The STATIC windows adjustment after the CALIBRATION procedure is a little bit different. It is shown in Table 15. The time management is explained in Figure 27.

	AIAF067A	Start_PAS_Calibration	0x047A, 0x075B, 0x05C2
00T00:09:10	AIAF063A	Stop_PAS_science
00T00:00:10	AIAF061B	Start_PAS_static_mode_science

Table 15: Adjust STATIC mode after CALIBRATION. The time intervals may vary.

image: 26_home_fedorov_SOLARORB_PAS_THE_BIBLE_COMMON_IMPORTANT_IMAGES_PAS_Calibration_timing_20220727.png

Figure 27: PAS calibration timing and 100 seconds boundaries

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SOLAR ORBITER SWA Proton-Alpha Analyzer (PAS) Main Reference Document (PAS Bible) V.3.0

1 The scope of this document and important references

2 General principles

2.1 Common View

2.4 PAS block-diagram and general configuration.

3 Design details

3.1 Mechanical Design

Ebanol-C coating

3.2 Detectors Board

3.3 HV Optic Board

3.4 FPGA

3.4.1 HV control

4.1 Pulse generator for EQM and PFM

4.2 CEM manipulations

4.2.1 How to set the HV on CEM

4.3 All versions of Sequencers and Configuration tables

4.4 Current version installed to DPU-PAS-PFM (20 Nov 2019)

5 COMMISSIONING special settings

5.1 Engineering mode table commissioning

6 DPU and CRUISE OPERATIONS

6.1.1 Normal mode default

6.1.2 BURST mode defaults

6.2 DPU - PAS state machine

6.3 MLT level PAS control

6.5.1 NORMAL MODE

6.5.2 BURST MODE

6.7 Special notes about STATIC mode

SOLAR ORBITER
SWA
Proton-Alpha Analyzer (PAS)
Main Reference Document (PAS Bible)
V.3.0