Level 1 Specification#

Spec muse-level1 version 1. Source: MUSEMW251165 via “MUSE FITS Keywords.xlsx”, sheet “L1 FITS”.

HDUs#

Name

Kind

Compression

COMPRESSED_IMAGE

compressed-image

RICE_1

Keywords (221 total, 182 required)#

compression (15)#

Keyword

Required

Type

Constraints

Source

Example

Comment

ZIMAGE

bool

one of True

T

extension contains compressed image; structural card owned by the FITS library

ZTENSION

str

one of IMAGE

IMAGE

Image extension; structural card owned by the FITS library

ZBITPIX

int

one of 16

16

data type of original image; structural card owned by the FITS library

ZNAXIS

int

one of 2

2

dimension of original image; structural card owned by the FITS library

ZNAXIS1

int

1036

length of original image axis; structural card owned by the FITS library

ZNAXIS2

int

548

length of original image axis; structural card owned by the FITS library

ZPCOUNT

int

0

number of parameters; structural card owned by the FITS library

ZGCOUNT

int

1

number of groups; structural card owned by the FITS library

ZTILE1

int

1036

size of tiles to be compressed; structural card owned by the FITS library

ZTILE2

int

1

size of tiles to be compressed; structural card owned by the FITS library

ZCMPTYPE

str

one of RICE_1

‘RICE_1 ‘

compression algorithm; structural card owned by the FITS library

ZNAME1

str

‘BLOCKSIZE’

compression block size; structural card owned by the FITS library

ZVAL1

int

32

pixels per block; structural card owned by the FITS library

ZNAME2

str

‘BYTEPIX ‘

bytes per pixel (1; structural card owned by the FITS library

ZVAL2

int

2

bytes per pixel (1; structural card owned by the FITS library

data (2)#

Keyword

Required

Type

Constraints

Source

Example

Comment

BTYPE

yes

str

‘Intensity’

BUNIT

yes

str

‘Corrected DN’

exposure (18)#

Keyword

Required

Type

Constraints

Source

Example

Comment

DATE-OBS

yes

str

isot

‘2024-11-08T00:59:04.234’

[ISO] Date when observation started; ISO 8; Keep due to IRIS heritage?

DATE-BEG

yes

str

isot

‘2024-11-08T00:59:04.234’

Start time of data in ISO 8601; Perferred over DATE-OBS (thompson 2015)

T_OBS

yes

str

isot

‘2024-11-08T00:59:04.383’

[ISO] Observation time

IMGFPT

yes

str

isot

‘2024-11-08T00:59:04.793’

[ISO] Telemetry First Packet Time

ISYSN

yes

int

1

System Number: CI=0,…; Redundant with CAMERA?

FSN

yes

int

136374300

Filtergram Sequence Number

FID

yes

int

65570

Filtergram ID

INSTRUME

yes

str

one of SG, CI

‘SG’

SG or CI

IMG_PATH

yes

Light path and SJI filter setting

IMG_TYPE

yes

str

one of LIGHT, DARK, LED, LTC, SPAT, VPAT

‘LIGHT ‘

Image type: LIGHT; DARK; LED; LTC; SPAT; VPAT

CAMERA

yes

str

one of CI, CI171, CI304, SG108, SG171, SG284

‘SG108’

CI, SG108, SG171, or SG 284; CI171/CI304 are prototype-era camera names retained until the C11 keyword reconciliation

SUMSPTRL

yes

int

2

CCD summing in spectral direction

SUMSPAT

yes

int

2

CCD summing in spatial direction

EXPTIME

yes

float

0.298752815

[sec] Exposure duration: mean shutter open time

EXPSDEV

yes

float

1.02368744E-4

[sec] Exposure standard deviation

INT_TIME

yes

float

0.515625

[sec] CCD integration duration

QUALLEV0

yes

int

Level 0 Quality word

QUALLEV1

yes

int

Level 1 Quality word

fits (15)#

Keyword

Required

Type

Constraints

Source

Example

Comment

XTENSION

str

one of BINTABLE

‘BINTABLE’

binary table extension; structural card owned by the FITS library

BITPIX

int

8

8-bit bytes; structural card owned by the FITS library

NAXIS

int

2

2-dimensional binary table; structural card owned by the FITS library

NAXIS1

int

8

width of table in bytes; structural card owned by the FITS library

NAXIS2

int

548

number of rows in table; structural card owned by the FITS library

PCOUNT

int

61099

size of special data area; structural card owned by the FITS library

GCOUNT

int

1

one data group (required keyword); structural card owned by the FITS library

TFIELDS

int

1

number of fields in each row; structural card owned by the FITS library

EXTNAME

str

one of COMPRESSED_IMAGE

COMPRESSED_IMAGE’

name of this binary table extension; structural card owned by the FITS library

BZERO

int

32768

structural card owned by the FITS library

BSCALE

int

1

structural card owned by the FITS library

TTYPE1

str

‘COMPRESSED_DATA’

structural card owned by the FITS library

TFORM1

str

‘1PB(295)’

structural card owned by the FITS library

CHECKSUM

yes

str

‘gAEnh8ClgAClg5Cl’

HDU checksum; required so the file self-validates on disk

DATASUM

yes

str

‘3204300732’

data unit checksum; required so the file self-validates on disk

isp-camera (14)#

Keyword

Required

Type

Constraints

Source

Example

Comment

MIMGSHCE

yes

M_IMG_SH_CMDED_EXPOSURE

MAECENA

yes

M_AEC_ENA

MAECFLFG

yes

M_AEC_FL_FLAG

MAECSGLP

yes

M_AEC_SG_LAPSE_TIME

SG AEC timeout to reset the exposure

MAECSGLG

yes

M_AEC_SG_LAG_TIME

MAECCILP

yes

M_AEC_CI_LAPSE_TIME

CI AEC timeout to reset the exposure

MAECCILG

yes

M_AEC_CI_LAG_TIME

MAEC_P

yes

M_AEC_P

MIHIS1

yes

M_IMG_HIST_BIN_1

Histogram count for bin 1

MIHIS2

yes

M_IMG_HIST_BIN_2

Histogram count for bin 2

MIHIS3

yes

M_IMG_HIST_BIN_3

Histogram count for bin 3

MIHIS4

yes

M_IMG_HIST_BIN_4

Histogram count for bin 4

MIHIS5

yes

M_IMG_HIST_BIN_5

Histogram count for bin 5

MIHISTN

yes

M_IMG_HIST_FRAME_SN

Image FSN of histogram

isp-mechanisms (17)#

Keyword

Required

Type

Constraints

Source

Example

Comment

MM_ENCP1

yes

M_MC_ENCODER_P1

MM_ENCP2

yes

M_MC_ENCODER_P2

MMFMCIP3

yes

M_MC_FMCI_P3

MMFMCICP

yes

M_MC_FMCI_CMDED_POS

CI focus mech. commanded pos

MMFMCIPS

yes

M_MC_FMCI_POS

CI focus mechanism current software position

MMFMGRP4

yes

M_MC_FMGR_P4

MMFCGRCP

yes

M_MC_FMGR_CMDED_POS

Grating focus mech. commanded pos

MMFMGRPS

yes

M_MC_FMGR_POS

Grating focus mechanism current software position

MMFMSLP3

yes

M_MC_FMSL_P3

MMFMSLCP

yes

M_MC_FMSL_CMDED_POS

Slit focus mech. commanded pos

MMFMSLPS

yes

M_MC_FMSL_POS

Slit focus mechanism current software position

MMWM1_CT

yes

M_MC_WM1_CMDED_TGT

wedge motor 1 commanded target value

MMWM1ENC

yes

M_MC_WM1_ENCODER

wedge motor 1 HW encoder position

MMWM1POS

yes

M_MC_WM1_POS

wedge motor 1 current software position

MMWM2_CT

yes

M_MC_WM2_CMDED_TGT

wedge motor 2 commanded target value

MMWM2ENC

yes

M_MC_WM2_ENCODER

wedge motor 2 HW encoder position

MMWM2POS

yes

M_MC_WM2_POS

wedge motor 2 current software position

isp-pointing (17)#

Keyword

Required

Type

Constraints

Source

Example

Comment

MIS_PZT1

yes

M_ISS_PZTOFF_P1

PZT P1 actuator offset value

MIS_PZT2

yes

M_ISS_PZTOFF_P2

PZT P2 actuator offset value

MIS_PZTA

yes

M_ISS_PZTOFFA

PZT A actuator offset value

MIS_PZTB

yes

M_ISS_PZTOFFB

PZT B actuator offset value

MIS_PZTC

yes

M_ISS_PZTOFFC

PZT C actuator offset value

MIS_CTRL

yes

int

M_ISS_CONTROL

7

ISS parameters (loop, diodes, offset range, gain)

MIS_DIOD

yes

int

M_ISS_DIODES

1

ISS diode: primary (1) or redundant (0)

MIS_LOOP

yes

M_ISS_LOOP

ISS loop: open (0) or closed (1) control

MIS_SRC

yes

M_ISS_SOURCE

LAMP (0 or high gain) or SUN (1 or low gain)

MIS_XERR

yes

M_ISS_X_ERROR

instantaneous ISS X axis error

MIS_XAVG

yes

M_ISS_X_ERROR_AVG

average of M_ISS_X_ERROR_MAPPED over one packet

MIS_XMAX

yes

M_ISS_X_ERROR_MAX

maximum of M_ISS_X_ERROR_MAPPED over one packet

MIS_XMIN

yes

M_ISS_X_ERROR_MIN

minimum of M_ISS_X_ERROR_MAPPED over one packet

MIS_YERR

yes

M_ISS_Y_ERROR

instantaneous ISS Y axis error

MIS_YAVG

yes

M_ISS_Y_ERROR_AVG

average of M_ISS_Y_ERROR_MAPPED over one packet

MIS_YMAX

yes

M_ISS_Y_ERROR_MAX

maximum of M_ISS_Y_ERROR_MAPPED over one packet

MIS_YMIN

yes

M_ISS_Y_ERROR_MIN

minimum of M_ISS_Y_ERROR_MAPPED over one packet

isp-sequencer (27)#

Keyword

Required

Type

Constraints

Source

Example

Comment

MSQFLTDX

yes

int

M_SQ_FLT_IDX

9

Frame list table current index

MSQFLTNX

yes

int

M_SQ_FLT_N_IDX

10

Frame list table number of indices

MSQFLTNR

yes

int

M_SQ_FLT_N_REPEAT

21

Frame list table number of repeats

MSQFLTRP

yes

int

M_SQ_FLT_REPEAT

4

Current frame list repeat index

MSQ_FSN

yes

M_SQ_FRAME_SN

ISP Frame sequence number

MSQSG108

yes

M_SQ_SG108_FDBT_ID

SG108 frame definition block

MSQSG171

yes

M_SQ_SG171_FDBT_ID

SG171 frame definition block

MSQSG284

yes

M_SQ_SG284_FDBT_ID

SG284 frame definition block

MSQOLTDX

yes

int

M_SQ_OLT_IDX

1

Observing list table current index

MSQOLTNX

yes

int

M_SQ_OLT_N_IDX

2

Observing list table number of of indices

MSQOLTNR

yes

int

M_SQ_OLT_N_REPEAT

22

Obsering list table number of repeats

MSQOLTRP

yes

int

M_SQ_OLT_REPEAT

3

Current observing list repeat index

MSQOEQSE

yes

int

M_SQ_ORB_EQ_SEC

2109645086

Equator crossing time, seconds

MSQOEQSS

yes

int

M_SQ_ORB_EQ_SUB

0

Equator crossing time, subseconds

MSQORBPD

yes

int

M_SQ_ORB_PERIOD

5828

[s] MUSE Orbital period

MSSGPZT1

yes

M_SQ_PZTSG_P1

SG PZT P1 total offset

MSQSGGWT

yes

M_SQ_OWTSG_ID

SG current orbital wobble table ID

MSQSGSRT

yes

int

M_SQ_SRTSG_ID

24312

SG Solar Rotation tracking table ID

MSSGPZTA

yes

M_SQ_PZTSG_A

SG PZT A total offset

MSSGPZTB

yes

M_SQ_PZTSG_B

SG PZT B total offset

MSSGPZTC

yes

M_SQ_PZTSG_C

SG PZT C total offset

MSCIPZT1

yes

M_SQ_PZTCI_P1

CI PZT P1 total offset

MSQCIGWT

yes

int

M_SQ_OWTCI_ID

20312

CI current orbital wobble table ID

MSQCISRT

yes

M_SQ_SRTCI_ID

CI Solar rotation tracking table ID

MSCIPZTA

yes

M_SQ_PZTCI_A

CI PZT A total offset

MSCIPZTB

yes

M_SQ_PZTCI_B

CI PZT B total offset

MSCIPZTC

yes

M_SQ_PZTCI_C

CI PZT C total offset

isp-thermal (15)#

Keyword

Required

Type

Constraints

Source

Example

Comment

MTCSGCCD

yes

M_TC_SGCCD

[C] SG CCD temperature

MTCSGCHD

yes

M_TC_SGCCDHEAD

[C] SG CCD head temperature

MTCSGCPR

yes

M_TC_SGCCDPRE

[C] SG CCD pre-amp temperature

MTCSGCEB

yes

M_TC_SGCEB

[C] SG elec. box temperature

MTCSG_PM

yes

M_TC_SGPM

[C] SG prime. mirror temperature

MTCSG_SL

yes

M_TC_SGSL

[C] SG slit temperature

MTCSG_GR

yes

M_TC_SGGR

[C] SG grating temperature

MTCGTOBJ

yes

M_TC_GTOBJ

[C] guide telescope temperature

MTCGTIEB

yes

M_TC_IEB

[C] IEB temperature

MCTCICCD

yes

M_TC_CICCD

[C] CI CCD temperature

MCTCICHD

yes

M_TC_CICCDHEAD

[C] CI CCD head temperature

MCTCICPR

yes

M_TC_CICCDPRE

[C] CI CCD pre-amp temperature

MCTCICEB

yes

M_TC_CICEB

[C] CI elec. Box temperature

MCTCI_PM

yes

M_TC_CIPM

[C] CI prime. mirror temperature

MCTCI_SM

yes

M_TC_CISM

[C] CI sec. mirror temperature

isp (3)#

Keyword

Required

Type

Constraints

Source

Example

Comment

ISPSNAME

yes

str

‘muse.isp’

ISP Series Name; Are these series a JSOC artifact?

ISPPKTIM

yes

str

isot

‘2024-11-08T00:59:04.661’

[ISO] PACKET_TIME for image status packet

ISPPKTVN

yes

str

‘010.058 ‘

PACKET_VERSION_NUMBER

observatory (9)#

Keyword

Required

Type

Constraints

Source

Example

Comment

FILENAME

yes

str

filename of the fits file

SOLARNET

yes

float

one of 0.0, 0.5, 1.0

0.5

at least partially SOLARNET compliant

OBS_HDU

yes

int

one of 1

1

Contains observational data

ORIGIN

yes

str

one of MUSE/LMSAL

‘MUSE/LMSAL’

TELESCOP

yes

str

one of MUSE

‘MUSE’

MUSE

BLD_VERS

yes

str

‘V9R5X ‘

Build Version: from xxx_version.h

LVL_NUM

yes

int

one of 1

1

same as LEVEL for IRIS legacy

LEVEL

yes

int

one of 1

1

data level

DATE

yes

str

isot

‘2024-11-08T16:59:51.000’

[ISO] Date_time of processing; ISO 8601

pointing (21)#

Keyword

Required

Type

Constraints

Source

Example

Comment

TIME_QBI

yes

str

isot

‘2025-10-01T00:00:04.662’

Packet time of the quateriion parameters

AEULRBRX

yes

float

8.4016002699999995E-2

Euler Angle Sun ref to S/C body frame X comp.

AEULRBRY

yes

float

0.28441301000000002

Euler Angle Sun ref to S/C body frame X comp.

AEULRBRZ

yes

float

7.8499998199999996E-4

Euler Angle Sun ref to S/C body frame X comp.

ACG_ROLL

yes

int

0

Roll profile commanded angle from solar north

OPHASE

yes

float

0.54705297900000005

Orbital phase

SAT_ROT

yes

float

7.8499998199999996E-4

Satellite roll angle: M_TAT_ACS_SC_ROLL

FLAT_REC

flatfield series record pointer; JSOC refrence???

ORB_REC

Orbit vector series record pointer; JSOC refrence???

RSUN_OBS

yes

float

957.88000488281205

[arcsec] apparent radius of the Sun seen at MUSE loc.

DSUN_OBS

yes

float

149788100000.84698

[m] Distance from MUSE to Sun center

GEIX_OBS

yes

float

2177500.6095787999

[m] Geocentric Equatorial Inertial x

GEIY_OBS

yes

float

-6616753.8780381503

[m] Geocentric Equatorial Inertial y

GEIZ_OBS

yes

float

-676401.96173936804

[m] Geocentric Equatorial Inertial z

HEIX_OBS

yes

float

-148431839336.996

[m] Heliocentric Equatorial Inertial x

HEIY_OBS

yes

float

-18451587397.969398

[m] Heliocentric Equatorial Inertial y

HEIZ_OBS

yes

float

-8000180892.0775299

[m] Heliocentric Equatorial Inertial z

OBS_VR

yes

float

-2064.40584080296

[m/s] Speed of observer in radial direction

HLZ

yes

int

0

High Latitude Flag

SAA

yes

int

1

South Atlantic Anomaly Flag

TEMP_REC

JSOC refrence???

readout (9)#

Keyword

Required

Type

Constraints

Source

Example

Comment

IICRSID

yes

int

936

Camera Readout Specification ID

CRS_DESC

yes

str

‘CI, 2x2, 0119’

CRS regions description: comma separated list

CRS_TYPE

CRS type; Redundant with CAMERA???

CRS_NREG

int

1

Number of CRS regions; Applicable for MUSE???

WIN_FLIP

yes

int

one of 0, 1, 2, 3

0

Window axis flip parameter; 0:none, 1:x, 2:y, 3: both

TSRN

Window start row for region N=1..8; Will MUSE have windowed readout??? (indexed keyword, N=1..8; expansion not yet modeled)

TERN

Window end row for region N=1..8 (indexed keyword, N=1..8; expansion not yet modeled)

TSCN

Window start column for region N=1..8 (indexed keyword, N=1..8; expansion not yet modeled)

TECN

Window end column for region N=1..8 (indexed keyword, N=1..8; expansion not yet modeled)

statistics (20)#

Keyword

Required

Type

Constraints

Source

Example

Comment

TOTVALS

yes

int

36100

Expected number of data values (pixels)

DATAVALS

yes

int

36100

Actual number of data values in image

MISSVALS

yes

int

0

Missing values: TOTVALS

PERCENTD

yes

int

100

Percent data; 100*DATAVALS

DATAMIN

yes

int

101

Minimum value of all pixels

DATAMAX

yes

int

216

Maximum value of all pixels

DATAMEDN

yes

int

110

Median value of all pixels

DATAMEAN

yes

float

114.620529

Mean value of all pixels

DATARMS

yes

float

12.355817800000001

Rms deviation from the mean value of all pixels

DATASKEW

yes

float

3.4021735199999901

Skewness from the mean value of all pixels

DATAKURT

yes

float

14.218980800000001

Kurtosis of all pixels

DATAP01

yes

int

106

1% level for histogram of pixel values

DATAP10

yes

int

108

10% level for histogram of pixel values

DATAP25

yes

int

115

25% level for histogram of pixel values

DATAP75

yes

int

162

75% level for histogram of pixel values

DATAP90

yes

int

178

90% level for histogram of pixel values

DATAP95

yes

int

187

95% level for histogram of pixel values

DATAP98

yes

int

197

98% level for histogram of pixel values

DATAP99

yes

int

207

99% level for histogram of pixel values

NSATPIX

yes

int

0

Number of saturated pixels

wcs (17)#

Keyword

Required

Type

Constraints

Source

Example

Comment

WCSNAME

yes

str

‘Helioprojective-cartesian’

Thompson A&A 449, 791 (2006); For more Windows add WCS sections

CTYPE1

yes

str

‘HPLN-TAN’

Axis label; for SG ‘WAVE’; In SGs, one section per slit?

CTYPE2

yes

str

‘HPLN-TAN’

Axis label

CNAME1

listed without details in the source sheet

CNAME2

listed without details in the source sheet

CRPIX1

yes

int

1

Reference pixel

CRPIX2

yes

int

1

Reference pixel

CUNIT1

yes

str

‘deg’

Angle in degrees; Angstrom for SGs?

CUNIT2

yes

str

‘deg’

Angle in degrees

CDELT1

yes

float

9.1669999999999995E-5

[deg|A] plate scale

CDELT2

yes

float

9.1669999999999995E-5

[deg] plate scale

PC1_1

yes

int

1

Rotation matrix

PC1_2

yes

int

0

Rotation matrix

PC2_1

yes

int

0

Rotation matrix

PC2_2

yes

int

1

Rotation matrix

CRVAL1

yes

int

0

[deg]

CRVAL2

yes

int

0

[deg]