.. _SIRCombinedSpectra: Combined Spectra Product ------------------------ Data product name ================= .. DataProductNameStart DpdSirCombinedSpectra .. DataProductNameEnd Data product custodian ====================== .. DataProductCustodianStart SIR .. DataProductCustodianEnd Data model tag ============== .. DataModelTagStart R-10.0 .. DataModelTagEnd Name of the Schema file ======================= .. NameSchemaStart .. raw:: html euc-sir-CombinedSpectra.xsd .. NameSchemaEnd Last Edited for DPDD Version ============================ .. LastEditedDPDDVersionStart 2.0 .. LastEditedDPDDVersionEnd Processing Elements Creating / Updating / Using the Product =========================================================== **Creators:** * SIR_Combine_Spectra Processing function using the data product ========================================== .. PFUsingStart SPE .. PFUsingEnd Proposed for inclusion in EAS/SAS ================================= This product is proposed for inclusion in the SAS: yes. Data product elements ===================== .. DataProductElementsStart :Header: object of type sys:genericHeader :Data: object of type sir:sirCombinedSpectra :QualityFlags: object of type dqc:sqfPlaceHolder :Parameters: object of type ppr:genericKeyValueParameters .. DataProductElementsEnd Detailed description of the data product ======================================== .. DetailedDescStart `SIR_Combine_Spectra pipeline` is triggered on a tile bases: there is 1 dpdCombinedSpectra for each dpdMerFinalCatalog. In the case where the MER catalog covers both a red and a blue field, we will have 2 CombinedSpectra: one RSG and one BGS. A single MER tile is covered by several exposures, once all the exposures that intersect that tile have been reduced by the `SIR_Extract_Spectra pipeline`, the `SIR_Combine_spectra pipeline` can be triggered, and the dpdCombinedSpectra data are produced. This product will contains a set of :ref:`SIRCombinedSpectrum`, one for each object contained in the MER catalog. It is stored as a collection of fits files, each file contains 1000 :ref:`SIRCombinedSpectrum`. The primary header of these fits files contains generic information such as: * the number of :ref:`SIRCombinedSpectrum` stored in the file * the tile ID * the lambda range of these spectra: RGS or BGS * the dictionary describing the bit mask .. table:: :width: 100% +----------------------------------------------------------------------------------------------------------------------------------------------------+ | **HDU** *PRIMARY*: header | +==========+===================+======================================================================================+==============================+ | | **Name** | **Description** | **Value** | +----------+-------------------+--------------------------------------------------------------------------------------+------------------------------+ | Keywords | FITS_DEF | | string = sir.combinedSpectra | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | FITS_VER | | string = 0.2 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | TELESCOP | | string = EUCLID | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | INSTRUME | or NISPsim for simulations | string = NISP | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | DATE | UT date when this file was created | string | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | ORIGIN | FITS file originator | string | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | SOFTVERS | Version of the processing function pipeline | string | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | VERSION | Data Release version | string | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | N_OBJ | Number of sources in file | integer | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | TILE_ID | MER tile index | integer | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | LRANGE | The grisms used in combination: BGS or RGS see definition simpleType = combinedGrism | string | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_GOOD | Mask bit position | integer = 0 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_NOT_USE | Mask bit position | integer = 1 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_LOW_SNR | Mask bit position | integer = 2 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_EXT_PRB | Mask bit position | integer = 4 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_HIGH | Mask bit position | integer = 8 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_LOW | Mask bit position | integer = 16 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_REL_FLUX | Mask bit position | integer = 32 | + +-------------------+--------------------------------------------------------------------------------------+------------------------------+ | | MSK_FLAG_ABS_FLUX | Mask bit position | integer = 64 | +----------+-------------------+--------------------------------------------------------------------------------------+------------------------------+ .. _SIRCombinedSpectrum: CombinedSpectrum ________________ A single CombinedSpectrum contains: * few meta data about the objects (:ref:`SIR_m_META`) * single ExtractedSpectra (:ref:`SIR_m_DITH1D_n_SIGNAL`) * information about contaminants affecting each ExtractedSpectra (:ref:`SIR_m_DITH1D_n_CONTAMINANTS`) * the combined spectrum obtained combining together all the ExtractedSpectra (:ref:`SIR_m_COMBINED1D_SIGNAL`) Each single CombinedSpectrum contained in the fits file is identified by an enumerative `m` and is stored as a collection of HDUs in the fits file. Each HDU associated to a give object starts with `m`. .. _CombinedFitsFigure: .. figure:: ./figures/combined.png : In the figure a part of CombinedSpectra. The CombinedSpectrum `m=995` (A) alongside the combined spectrum, it contains 5 dither extracted spectra and their respective contaminants. The CombinedSpectrum `m=997` (B) is an example of empty CombinedSpectrum. .. _SIR_m_META: m_META ~~~~~~ This is the content of the `m_META` HDU: .. table:: :width: 100% +------------------------------------------------------------------------------------+ | **HDU** *m_META*: header | +==========+==========+==================================================+===========+ | | **Name** | **Description** | **Value** | +----------+----------+--------------------------------------------------+-----------+ | Keywords | N_DITH | Number of dither containing object, was DITH_NUM | integer | + +----------+--------------------------------------------------+-----------+ | | OBJ_ID | MER-specified identifier of the m-th object | integer | + +----------+--------------------------------------------------+-----------+ | | RA_OBJ | R.A. of the m-th object | double | + +----------+--------------------------------------------------+-----------+ | | DEC_OBJ | Declination of the m-th object | double | +----------+----------+--------------------------------------------------+-----------+ **NOTE:** if no spectra are extracted for a given object, the CombinedSpectrum is empty and it consists of this single extension. (See the **B** example in the figure :numref:`CombinedFitsFigure`) .. _SIR_m_DITH1D_n_SIGNAL: m_DITH1D_n_SIGNAL ~~~~~~~~~~~~~~~~~ For each spectrum `m`, there is a variable number of `m_DITH1D_n_SIGNAL` spectra; the number of these spectra depends on the number of exposures containing the spectrum of object `m`. Each `m_DITH1D_n_SIGNAL` is identified by the pointing ID `n`. In the example **A** of the figure :numref:`CombinedFitsFigure` `n` is: 3197, 3198, 3199, 3318, 3319. The header of `m_DITH1D_n_SIGNAL` contains info about the origin of this spectrum: .. table:: :width: 100% +-------------------------------------------------------------------------------------------------+ | **HDU** *m_DITH1D_n_SIGNAL*: header | +==========+==========+===============================================================+===========+ | | **Name** | **Description** | **Value** | +----------+----------+---------------------------------------------------------------+-----------+ | Keywords | EXTNAME | | string | + +----------+---------------------------------------------------------------+-----------+ | | GWA_POS | GWA position (RGS270,RGS000,RGS180,BGS000,OPEN) | string | + +----------+---------------------------------------------------------------+-----------+ | | GWA_TILT | Commanded Grism Tilt Angle | integer | + +----------+---------------------------------------------------------------+-----------+ | | DITH_ID | The dither index | integer | + +----------+---------------------------------------------------------------+-----------+ | | PTGID | Pointing ID in the name | integer | + +----------+---------------------------------------------------------------+-----------+ | | EXPTIME | Exposure time | double | + +----------+---------------------------------------------------------------+-----------+ | | FSCALE | Scaling factor | double | + +----------+---------------------------------------------------------------+-----------+ | | WMIN | Minimum wavelength of the binning | double | + +----------+---------------------------------------------------------------+-----------+ | | BINWIDTH | Wavelength bin width | double | + +----------+---------------------------------------------------------------+-----------+ | | BINCOUNT | Wavelength bin count | double | + +----------+---------------------------------------------------------------+-----------+ | | DET_ID | The detector index | integer | + +----------+---------------------------------------------------------------+-----------+ | | DET_ID_2 | Additional detector involved | integer | + +----------+---------------------------------------------------------------+-----------+ | | LSF_SIG | Standard deviation of the Gaussian Line Spread Function model | double | + +----------+---------------------------------------------------------------+-----------+ | | EXT_PROF | 1D extraction profile used (NONE,OPT_THUMB,OPT_PSF) | string | +----------+----------+---------------------------------------------------------------+-----------+ If the spectrum was entirely contained in a single detector, the `DET_ID_2` keyword will be missing; otherwise, if it is present, it means the extracted spectrum spanned across two detectors (part on `DET_ID` and part on `DET_ID_2`). The `m_DITH1D_n_SIGNAL` is organized as binary table and it contains the following columns: * **WAVELENGTH**: the spectrum wavelengths bin [:math:`\mathring{A}`] * **SIGNAL**: the spectrum fluxes bin [:math:`{erg}\ {cm^{-2}} s^{-1} \mathring{A}^{-1}`]. Fluxes stored in this column are scaled by the `FSCALE` factor written in Header. * **MASK**: the bit mask for the current flux bin. The definition of this bit mask is stored in the Primary Header (see `MSK_*` keywords). * **VAR**: the variances associate to the fluxes [:math:`{erg^2} {cm^{-4}} s^{-2} \mathring{A}^{-2}`]. (The `FSCALE` scaling factor must also be taken into account for this column). * **QUALITY**: each flux bin of an extracted 1D spectrum is obtained by combining different pixels from the input frame (2D extraction), and by combining different points of the 2D spectrum (1D extraction). During these two extraction processes, not all available pixels are used (bad pixels, cosmic rays, etc. are excluded). Moreover not all pixels are used with the same weights both in the 2D resampling and the 1D extraction. This quality value is a number between 0 and 1 that accounts for *how many pixels were used* to obtain this flux bin: it is the ratio between the weighted sum of the pixels actually used and the weighted sum of the pixels potentially available to obtain this bin. Quality 1 means all available pixels were used, 0 means no pixels were used. .. _SIR_m_DITH1D_n_CONTAMINANTS: m_DITH1D_n_CONTAMINANTS ~~~~~~~~~~~~~~~~~~~~~~~ These extensions are associated to :ref:`SIR_m_DITH1D_n_SIGNAL` extensions; this extension is a table which contains the list of contaminants of the `m_DITH1D_n_SIGNAL` spectra. .. table:: :width: 100% +-----------------------------------------------------------------------------------+ | **HDU** *m_DITH1D_n_CONTAMINANTS*: header | +==========+==========+=================================================+===========+ | | **Name** | **Description** | **Value** | +----------+----------+-------------------------------------------------+-----------+ | Keywords | EXTNAME | | string | + +----------+-------------------------------------------------+-----------+ | | GWA_POS | GWA position (RGS270,RGS000,RGS180,BGS000,OPEN) | string | + +----------+-------------------------------------------------+-----------+ | | GWA_TILT | Commanded Grism Tilt Angle | integer | + +----------+-------------------------------------------------+-----------+ | | DITH_ID | The dither index | integer | + +----------+-------------------------------------------------+-----------+ | | PTGID | Pointing ID in the name | integer | +----------+----------+-------------------------------------------------+-----------+ .. table:: :width: 100% +-----------------------------------------------------------------------------------+ | **HDU** *m_DITH1D_n_CONTAMINANTS*: 1 columns table | +=========+==========+===================================+==========+===============+ | | **Name** | **Description** | **Unit** | **Format** | +---------+----------+-----------------------------------+----------+---------------+ | Columns | OBJ_ID | Object ID of contaminant, int 64 | NA | FITS *K* | +---------+----------+-----------------------------------+----------+---------------+ .. _SIR_m_COMBINED1D_SIGNAL: m_COMBINED1D_SIGNAL ~~~~~~~~~~~~~~~~~~~ This extension contains the combined spectrum obtained combining all the related :ref:`SIR_m_DITH1D_n_SIGNAL`; this spectrum is stored as Binary Table HDU. .. table:: :width: 100% +-----------------------------------------------------------------------------------------------------------+ | **HDU** *m_COMBINED1D_SIGNAL*: header | +==========+==========+======================================================================+==============+ | | **Name** | **Description** | **Value** | +----------+----------+----------------------------------------------------------------------+--------------+ | Keywords | EXTNAME | | string | + +----------+----------------------------------------------------------------------+--------------+ | | EXPTIME | Exposure time | double | + +----------+----------------------------------------------------------------------+--------------+ | | FSCALE | Scaling factor | double | + +----------+----------------------------------------------------------------------+--------------+ | | WMIN | Minimum wavelength of the binning | double | + +----------+----------------------------------------------------------------------+--------------+ | | BINWIDTH | Wavelength bin width | double | + +----------+----------------------------------------------------------------------+--------------+ | | BINCOUNT | Wavelength bin count | integer | + +----------+----------------------------------------------------------------------+--------------+ | | LSF_SIG | Standard deviation of the Gaussian Line Spread Function model | double | + +----------+----------------------------------------------------------------------+--------------+ | | EXT_PROF | 1D extraction profile used (NONE,OPT_THUMB,OPT_PSF) | string | +----------+----------+----------------------------------------------------------------------+--------------+ .. table:: :width: 100% +-----------------------------------------------------------------------------------------------------------+ | **HDU** *m_COMBINED1D_SIGNAL*: 6 columns table | +=========+============+===============================================+=======================+============+ | | **Name** | **Description** | **Unit** | **Format** | +---------+------------+-----------------------------------------------+-----------------------+------------+ | Columns | WAVELENGTH | Wavelength column, was WBIN | Angstrom | FITS *E* | + +------------+-----------------------------------------------+-----------------------+------------+ | | SIGNAL | Fluxes column | erg/s/cm2/Angstrom | FITS *E* | + +------------+-----------------------------------------------+-----------------------+------------+ | | MASK | Pixel mask column, int 32 | Number | FITS *J* | + +------------+-----------------------------------------------+-----------------------+------------+ | | VAR | Variance on fluxes | erg2/s2/cm4/Angstrom2 | FITS *E* | + +------------+-----------------------------------------------+-----------------------+------------+ | | QUALITY | Pixel quality flag column, float 32 | Number | FITS *E* | + +------------+-----------------------------------------------+-----------------------+------------+ | | NDITH | Number of spectra used in combination, int 16 | Number | FITS *I* | +---------+------------+-----------------------------------------------+-----------------------+------------+ This table contains all the columns of the :ref:`SIR_m_DITH1D_n_SIGNAL` plus the additional column **NDITH**. This **NDITH** columns contains the number of spectra which contributed to obtain the current flux bin. By definition the values of this column are lower equal than `N_DITH` keyword: the `N_DITH` keyword gives a global information, **NDITH** columns gives this information for each bin. .. DetailedDescEnd