예제 #1
0
def instrument_simulator(input_events,
                         out_file,
                         exp_time,
                         instrument,
                         sky_center,
                         overwrite=False,
                         instr_bkgnd=True,
                         foreground=True,
                         ptsrc_bkgnd=True,
                         bkgnd_file=None,
                         no_dither=False,
                         dither_params=None,
                         roll_angle=0.0,
                         subpixel_res=False,
                         aimpt_shift=None,
                         prng=None):
    """
    Take unconvolved events and create an event file from them. This
    function calls generate_events to do the following:

    1. Determines which events are observed using the ARF
    2. Pixelizes the events, applying PSF effects and dithering
    3. Determines energy channels using the RMF

    and then calls make_background to add instrumental and astrophysical
    backgrounds, unless a background file is provided, in which case
    the background events are read from this file. The events are
    then written out to a file.

    Parameters
    ----------
    input_events : string, dict, or None
        The unconvolved events to be used as input. Can be one of the
        following:
        1. The name of a SIMPUT catalog file.
        2. A Python dictionary containing the following items:
        "ra": A NumPy array of right ascension values in degrees.
        "dec": A NumPy array of declination values in degrees.
        "energy": A NumPy array of energy values in keV.
        "flux": The flux of the entire source, in units of erg/cm**2/s.
    out_file : string
        The name of the event file to be written.
    exp_time : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`
        The exposure time to use, in seconds. 
    instrument : string
        The name of the instrument to use, which picks an instrument
        specification from the instrument registry. 
    sky_center : array, tuple, or list
        The center RA, Dec coordinates of the observation, in degrees.
    overwrite : boolean, optional
        Whether or not to overwrite an existing file with the same name.
        Default: False
    instr_bkgnd : boolean, optional
        Whether or not to include the instrumental/particle background. 
        Default: True
    foreground : boolean, optional
        Whether or not to include the local foreground. 
        Default: True
    ptsrc_bkgnd : boolean, optional
        Whether or not to include the point-source background. 
        Default: True
    bkgnd_file : string, optional
        If set, backgrounds will be loaded from this file and not generated
        on the fly. Default: None
    no_dither : boolean, optional
        If True, turn off dithering entirely. Default: False
    dither_params : array-like of floats, optional
        The parameters to use to control the size and period of the dither
        pattern. The first two numbers are the dither amplitude in x and y
        detector coordinates in arcseconds, and the second two numbers are
        the dither period in x and y detector coordinates in seconds. 
        Default: [8.0, 8.0, 1000.0, 707.0].
    roll_angle : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`, optional
        The roll angle of the observation in degrees. Default: 0.0
    subpixel_res: boolean, optional
        If True, event positions are not randomized within the pixels 
        within which they are detected. Default: False
    aimpt_shift : array-like, optional
        A two-float array-like object which shifts the aimpoint on the 
        detector from the nominal position. Units are in arcseconds.
        Default: None, which results in no shift from the nominal aimpoint. 
    prng : :class:`~numpy.random.RandomState` object, integer, or None
        A pseudo-random number generator. Typically will only 
        be specified if you have a reason to generate the same 
        set of random numbers, such as for a test. Default is None, 
        which sets the seed based on the system time. 

    Examples
    --------
    >>> instrument_simulator("sloshing_simput.fits", "sloshing_evt.fits", 
    ...                      300000.0, "lynx_hdxi", [30., 45.], overwrite=True)
    """
    from soxs.background import add_background_from_file
    if not out_file.endswith(".fits"):
        out_file += ".fits"
    mylog.info(f"Making observation of source in {out_file}.")
    # Make the source first
    events, event_params = generate_events(input_events,
                                           exp_time,
                                           instrument,
                                           sky_center,
                                           no_dither=no_dither,
                                           dither_params=dither_params,
                                           roll_angle=roll_angle,
                                           subpixel_res=subpixel_res,
                                           aimpt_shift=aimpt_shift,
                                           prng=prng)
    # If the user wants backgrounds, either make the background or add an already existing
    # background event file. It may be necessary to reproject events to a new coordinate system.
    if bkgnd_file is None:
        if not instr_bkgnd and not ptsrc_bkgnd and not foreground:
            mylog.info("No backgrounds will be added to this observation.")
        else:
            mylog.info("Adding background events.")
            bkg_events, _ = make_background(exp_time,
                                            instrument,
                                            sky_center,
                                            foreground=foreground,
                                            instr_bkgnd=instr_bkgnd,
                                            no_dither=no_dither,
                                            dither_params=dither_params,
                                            ptsrc_bkgnd=ptsrc_bkgnd,
                                            prng=prng,
                                            subpixel_res=subpixel_res,
                                            roll_angle=roll_angle,
                                            aimpt_shift=aimpt_shift)
            for key in events:
                events[key] = np.concatenate([events[key], bkg_events[key]])
    else:
        mylog.info(f"Adding background events from the file {bkgnd_file}.")
        if not os.path.exists(bkgnd_file):
            raise IOError(
                f"Cannot find the background event file {bkgnd_file}!")
        events = add_background_from_file(events, event_params, bkgnd_file)
    if len(events["energy"]) == 0:
        raise RuntimeError(
            "No events were detected from source or background!!")
    write_event_file(events, event_params, out_file, overwrite=overwrite)
    mylog.info("Observation complete.")
예제 #2
0
def instrument_simulator(input_events, out_file, exp_time, instrument,
                         sky_center, overwrite=False, instr_bkgnd=True, 
                         foreground=True, ptsrc_bkgnd=True, 
                         bkgnd_file=None, no_dither=False, 
                         dither_params=None, roll_angle=0.0, 
                         subpixel_res=False, prng=None):
    """
    Take unconvolved events and create an event file from them. This
    function calls generate_events to do the following:

    1. Determines which events are observed using the ARF
    2. Pixelizes the events, applying PSF effects and dithering
    3. Determines energy channels using the RMF

    and then calls make_background to add instrumental and astrophysical
    backgrounds, unless a background file is provided, in which case
    the background events are read from this file. The events are
    then written out to a file.

    Parameters
    ----------
    input_events : string, dict, or None
        The unconvolved events to be used as input. Can be one of the
        following:
        1. The name of a SIMPUT catalog file.
        2. A Python dictionary containing the following items:
        "ra": A NumPy array of right ascension values in degrees.
        "dec": A NumPy array of declination values in degrees.
        "energy": A NumPy array of energy values in keV.
        "flux": The flux of the entire source, in units of erg/cm**2/s.
    out_file : string
        The name of the event file to be written.
    exp_time : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`
        The exposure time to use, in seconds. 
    instrument : string
        The name of the instrument to use, which picks an instrument
        specification from the instrument registry. 
    sky_center : array, tuple, or list
        The center RA, Dec coordinates of the observation, in degrees.
    overwrite : boolean, optional
        Whether or not to overwrite an existing file with the same name.
        Default: False
    instr_bkgnd : boolean, optional
        Whether or not to include the instrumental/particle background. 
        Default: True
    foreground : boolean, optional
        Whether or not to include the local foreground. 
        Default: True
    ptsrc_bkgnd : boolean, optional
        Whether or not to include the point-source background. 
        Default: True
    bkgnd_file : string, optional
        If set, backgrounds will be loaded from this file and not generated
        on the fly. Default: None
    no_dither : boolean, optional
        If True, turn off dithering entirely. Default: False
    dither_params : array-like of floats, optional
        The parameters to use to control the size and period of the dither
        pattern. The first two numbers are the dither amplitude in x and y
        detector coordinates in arcseconds, and the second two numbers are
        the dither period in x and y detector coordinates in seconds. 
        Default: [8.0, 8.0, 1000.0, 707.0].
    roll_angle : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`, optional
        The roll angle of the observation in degrees. Default: 0.0
    subpixel_res: boolean, optional
        If True, event positions are not randomized within the pixels 
        within which they are detected. Default: False
    prng : :class:`~numpy.random.RandomState` object, integer, or None
        A pseudo-random number generator. Typically will only 
        be specified if you have a reason to generate the same 
        set of random numbers, such as for a test. Default is None, 
        which sets the seed based on the system time. 

    Examples
    --------
    >>> instrument_simulator("sloshing_simput.fits", "sloshing_evt.fits", 
    ...                      300000.0, "hdxi_3x10", [30., 45.], overwrite=True)
    """
    from soxs.background import add_background_from_file
    if not out_file.endswith(".fits"):
        out_file += ".fits"
    mylog.info("Making observation of source in %s." % out_file)
    # Make the source first
    events, event_params = generate_events(input_events, exp_time, instrument, sky_center,
                                           no_dither=no_dither, dither_params=dither_params, 
                                           roll_angle=roll_angle, subpixel_res=subpixel_res, 
                                           prng=prng)
    # If the user wants backgrounds, either make the background or add an already existing
    # background event file. It may be necessary to reproject events to a new coordinate system.
    if bkgnd_file is None:
        if not instr_bkgnd and not ptsrc_bkgnd and not foreground:
            mylog.info("No backgrounds will be added to this observation.")
        else:
            mylog.info("Adding background events.")
            bkg_events, _ = make_background(exp_time, instrument, sky_center,
                                            foreground=foreground, instr_bkgnd=instr_bkgnd, 
                                            no_dither=no_dither, dither_params=dither_params, 
                                            ptsrc_bkgnd=ptsrc_bkgnd, prng=prng, 
                                            subpixel_res=subpixel_res, roll_angle=roll_angle)
            for key in events:
                events[key] = np.concatenate([events[key], bkg_events[key]])
    else:
        mylog.info("Adding background events from the file %s." % bkgnd_file)
        if not os.path.exists(bkgnd_file):
            raise IOError("Cannot find the background event file %s!" % bkgnd_file)
        events = add_background_from_file(events, event_params, bkgnd_file)
    if len(events["energy"]) == 0:
        raise RuntimeError("No events were detected from source or background!!")
    write_event_file(events, event_params, out_file, overwrite=overwrite)
    mylog.info("Observation complete.")
예제 #3
0
def make_background_file(out_file,
                         exp_time,
                         instrument,
                         sky_center,
                         overwrite=False,
                         foreground=True,
                         instr_bkgnd=True,
                         ptsrc_bkgnd=True,
                         no_dither=False,
                         dither_params=None,
                         subpixel_res=False,
                         input_sources=None,
                         absorb_model="wabs",
                         nH=0.05,
                         prng=None):
    """
    Make an event file consisting entirely of background events. This will be 
    useful for creating backgrounds that can be added to simulations of sources.

    Parameters
    ----------
    exp_time : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`
        The exposure time to use, in seconds. 
    instrument : string
        The name of the instrument to use, which picks an instrument
        specification from the instrument registry. 
    sky_center : array, tuple, or list
        The center RA, Dec coordinates of the observation, in degrees.
    overwrite : boolean, optional
        Whether or not to overwrite an existing file with the same name.
        Default: False
    foreground : boolean, optional
        Whether or not to include the Galactic foreground. Default: True
    instr_bkgnd : boolean, optional
        Whether or not to include the instrumental background. Default: True
    ptsrc_bkgnd : boolean, optional
        Whether or not to include the point-source background. Default: True
    no_dither : boolean, optional
        If True, turn off dithering entirely. Default: False
    dither_params : array-like of floats, optional
        The parameters to use to control the size and period of the dither
        pattern. The first two numbers are the dither amplitude in x and y
        detector coordinates in arcseconds, and the second two numbers are
        the dither period in x and y detector coordinates in seconds. 
        Default: [8.0, 8.0, 1000.0, 707.0].
    subpixel_res: boolean, optional
        If True, event positions are not randomized within the pixels 
        within which they are detected. Default: False
    input_sources : string, optional
        If set to a filename, input the point source positions, fluxes,
        and spectral indices from an ASCII table instead of generating
        them. Default: None
    absorb_model : string, optional
        The absorption model to use, "wabs" or "tbabs". Default: "wabs"
    nH : float, optional
        The hydrogen column in units of 10**22 atoms/cm**2. 
        Default: 0.05
    prng : :class:`~numpy.random.RandomState` object, integer, or None
        A pseudo-random number generator. Typically will only 
        be specified if you have a reason to generate the same 
        set of random numbers, such as for a test. Default is None, 
        which sets the seed based on the system time. 
    """
    prng = parse_prng(prng)
    events, event_params = make_background(exp_time,
                                           instrument,
                                           sky_center,
                                           ptsrc_bkgnd=ptsrc_bkgnd,
                                           foreground=foreground,
                                           instr_bkgnd=instr_bkgnd,
                                           no_dither=no_dither,
                                           dither_params=dither_params,
                                           subpixel_res=subpixel_res,
                                           input_sources=input_sources,
                                           absorb_model=absorb_model,
                                           nH=nH,
                                           prng=prng)
    write_event_file(events, event_params, out_file, overwrite=overwrite)
예제 #4
0
def make_background_file(out_file, exp_time, instrument, sky_center,
                         overwrite=False, foreground=True, instr_bkgnd=True,
                         ptsrc_bkgnd=True, no_dither=False, dither_params=None,
                         subpixel_res=False, input_sources=None, 
                         absorb_model="wabs", nH=0.05, prng=None):
    """
    Make an event file consisting entirely of background events. This will be 
    useful for creating backgrounds that can be added to simulations of sources.

    Parameters
    ----------
    exp_time : float, (value, unit) tuple, or :class:`~astropy.units.Quantity`
        The exposure time to use, in seconds. 
    instrument : string
        The name of the instrument to use, which picks an instrument
        specification from the instrument registry. 
    sky_center : array, tuple, or list
        The center RA, Dec coordinates of the observation, in degrees.
    overwrite : boolean, optional
        Whether or not to overwrite an existing file with the same name.
        Default: False
    foreground : boolean, optional
        Whether or not to include the Galactic foreground. Default: True
    instr_bkgnd : boolean, optional
        Whether or not to include the instrumental background. Default: True
    ptsrc_bkgnd : boolean, optional
        Whether or not to include the point-source background. Default: True
    no_dither : boolean, optional
        If True, turn off dithering entirely. Default: False
    dither_params : array-like of floats, optional
        The parameters to use to control the size and period of the dither
        pattern. The first two numbers are the dither amplitude in x and y
        detector coordinates in arcseconds, and the second two numbers are
        the dither period in x and y detector coordinates in seconds. 
        Default: [8.0, 8.0, 1000.0, 707.0].
    subpixel_res: boolean, optional
        If True, event positions are not randomized within the pixels 
        within which they are detected. Default: False
    input_sources : string, optional
        If set to a filename, input the point source positions, fluxes,
        and spectral indices from an ASCII table instead of generating
        them. Default: None
    absorb_model : string, optional
        The absorption model to use, "wabs" or "tbabs". Default: "wabs"
    nH : float, optional
        The hydrogen column in units of 10**22 atoms/cm**2. 
        Default: 0.05
    prng : :class:`~numpy.random.RandomState` object, integer, or None
        A pseudo-random number generator. Typically will only 
        be specified if you have a reason to generate the same 
        set of random numbers, such as for a test. Default is None, 
        which sets the seed based on the system time. 
    """
    prng = parse_prng(prng)
    events, event_params = make_background(exp_time, instrument, sky_center, 
                                           ptsrc_bkgnd=ptsrc_bkgnd, 
                                           foreground=foreground, 
                                           instr_bkgnd=instr_bkgnd,
                                           no_dither=no_dither,
                                           dither_params=dither_params, 
                                           subpixel_res=subpixel_res,
                                           input_sources=input_sources,
                                           absorb_model=absorb_model,
                                           nH=nH, prng=prng)
    write_event_file(events, event_params, out_file, overwrite=overwrite)