.. _filters: Defining filters =================== bayesn-td includes a selection of filters and standards for convenience. Alternatively, you can use your own through a simple YAML file, allowing new or updated filters to be easily implemented independently of updates to the package. Built-in filters ----------------- bayesn-td includes the following filters, grouped by instrument, survey, or system. The name shown is the string to use when referring to the filter within bayesn-td (e.g. ``g_PS1`` for Pan-STARRS 1 *g*-band). If the names in your data files do not match these, you can provide a ``band_map`` to match them up, as discussed in :ref:`fitting`. - Standard - Stritzinger *UBVRI* filters - Names: ``U``, ``B``, ``V``, ``R``, ``I`` - Source: Stritzinger+11, 2005PASP..117..810S - 2MASS Peters Automated Infrared Imaging Telescope *JHK* filters - Names: ``J``, ``H``, ``K`` - Source: Cohen+03, 2003AJ....126.1090C - Persson *YJHK* filters - Names: ``Y_P``, ``J_P``, ``H_P``, ``K_P`` - Source: 1998AJ....116.2475P - CSP - Carnegie Supernova Project *BVgri* Swope filters - Names: ``B_CSP``, ``V_CSP``, ``V_CSP_3009``, ``V_CSP_3014``, ``g_CSP``, ``r_CSP``, ``i_CSP`` - Source: Krisciunas+17, 2017AJ....154..211K, https://csp.obs.carnegiescience.edu/data/filters - Carnegie Supernova Project II *BVgri* Swope filters - Names: ``B_CSP2``, ``V_CSP2``, ``g_CSP2``, ``r_CSP2``, ``i_CSP2`` - Source: https://csp.obs.carnegiescience.edu/data/filters - Swope RetroCam *YJH* filters - Names: ``Y_RC``, ``J_RC1``, ``J_RC2``, ``H_RC`` - Source: Krisciunas+17, 2017AJ....154..211K, https://csp.obs.carnegiescience.edu/data/filters - Dupont WIRC *YJH* filters - Names: ``Y_WIRC``, ``J_WIRC``, ``H_WIRC`` - Source: Krisciunas+17, 2017AJ....154..211K, https://csp.obs.carnegiescience.edu/data/filters - Dupont RetroCam *YJH* filters - Names: ``Y_RCDP``, ``J_RCDP``, ``H_RCDP`` - Source: https://csp.obs.carnegiescience.edu/data/filters - DECam - Dark Energy Camera at Cerro Tololo Inter-American Observatory *griz* filters - Names: ``g_DES``, ``r_DES``, ``i_DES``, ``z_DES`` - Source: https://noirlab.edu/science/programs/ctio/filters/Dark-Energy-Camera - HST - Hubble Space Telescope WFC3 IR/UVIS2 filters - Names: ``F105W``, ``F125W``, ``F140W``, ``F160W``, ``F225W``, ``F275W``, ``F300X``, ``F336W``, ``F390W``, ``F438W``, ``F475W``, ``F555W``, ``F625W``, ``F814W`` - Source: https://www.stsci.edu/hst/instrumentation/wfc3/performance/throughputs - JWST - NIRCam broad-band filters - Names: ``F090W``, ``F115W``, ``F150W``, ``F200W``, ``F277W``, ``F356W``, ``F444W`` - Source: STScI - LSST - Legacy Survey of Space and Time at Vera Rubin Observatory *ugrizy* filters - Names: ``u_LSST``, ``g_LSST``, ``r_LSST``, ``i_LSST``, ``z_LSST``, ``y_LSST`` - Source: https://github.com/lsst/throughputs - PS1 - Pan-STARRS 1 *grizy* filters - Names: ``g_PS1``, ``r_PS1``, ``i_PS1``, ``z_PS1``, ``y_PS1`` - Source: Tonry+12, 2012ApJ...750...99T - Roman - Wide Field Instrument (WFI) filters - Names: ``roman::Z``, ``roman::Y``, ``roman::J``, ``roman::H``, ``roman::F``, ``roman::R`` - SWIFT UVOT - UVOT *UBV* and UV filters - Names: ``U_SWIFT``, ``B_SWIFT``, ``V_SWIFT``, ``UVW1``, ``UVW2``, ``UVM2`` - Source: Poole+08, 2008MNRAS.383..627P - USNO - United States Naval Observatory 40-inch telescope *u'g'r'i'z'* filters - Names: ``u_prime``, ``g_prime``, ``r_prime``, ``i_prime``, ``z_prime`` - Source: Fukugita+96, 1996AJ....111.1748F; Smith+02, 2002AJ....123.2121S - ZTF - Zwicky Transient Facility *gri* filters - Names: ``p48g``, ``p48r``, ``p48i`` - Source: Bellm+19, 2019PASP..131a8002B - ANDICAM - ANDICAM at Cerro Tololo Inter-American Observatory *YJHK* filters - Names: ``Y_AND``, ``J_AND``, ``H_AND``, ``K_AND`` For a complete listing of all available filters, inspect the bundled ``filters.yaml`` file in the bayesn-td package directory. Specifying custom filters --------------------------- You can add custom filters beyond those built in by providing a filter YAML file via the ``filter_yaml`` argument when initialising the model, or the ``--filters`` command-line argument. Custom filters are included alongside the built-in ones, so you can mix and match. If you give a custom filter the same name as a built-in one, your custom filter will take precedence. The filter YAML file should have the following structure: .. code-block:: yaml standards_root: /path/to/standards standards: vega: path: vega_standard.fits bd17: path: bd17_standard.fits filters_root: /path/to/filters filters: my_band_1: magsys: ab magzero: 0 path: my_band_1_response.dat lam_unit: nm my_band_2: magsys: vega magzero: 0 path: my_band_2_response.dat - ``standards_root`` — root directory for standard spectra (optional; paths can be absolute). - ``standards`` — defines reference spectra for magnitude systems. Each entry needs a ``path`` to a FITS or text file with WAVELENGTH and FLUX columns. - ``filters_root`` — root directory for filter response files (optional). - ``filters`` — defines the filters. Each entry requires: - ``magsys`` — magnitude system (``ab``, ``vega``, ``bd17``, or a custom standard name). - ``magzero`` — magnitude offset. - ``path`` — path to the filter response file. - ``lam_unit`` — wavelength unit in the response file. Default is Angstroms; set to ``nm`` or ``micron`` if needed. Automatic filter dropping -------------------------- The wavelength range covered by the model depends on which pre-trained model you use (see :ref:`models`). Filters are automatically dropped for individual SNe when they fall outside the rest-frame wavelength range at the source redshift. The cut-off wavelengths for each filter are defined as the wavelength where the filter response first drops below 1 per cent of its maximum value.