Sasmirala Individual Information for NGC 5953

Description

NGC 5953 is a lenticular galaxy at a redshift of z = 0.0066 (D ~ 31.4 Mpc) which heavily interacts with NGC 5954 to the north-east at a projected distance of D = ~ 43arcsec (~ 6 kpc). BOth galaxies form the pair Arp 91 (see [casasola_molecular_2010] for a recent detailed study). NGC 5953 hosts an AGN optically classified either as a Sy 2 [gonzalez_delgado_circumnuclear_1996, goncalves_agns_1999], LINER [veilleux_optical_1995, kim_optical_1995], or AGN/starburst composite [veron_agns_1997]. The AGN is embedded within a disc-like circum-nuclear starburst with a diameter of ~ 12arcsec ~ 1.8 kpc [gonzalez_delgado_circumnuclear_1996, casasola_molecular_2010] Nuclear X-ray emission is only detected in the soft band [guainazzi_x-ray_2005, lamassa_uncovering_2011] A compact radio core with jet-like extension of ~ 1arcsec in PA~ 20∘ [jenkins_arp_1984, krips_nuclei_2007] and roughly cospatial [O III] emission are present. [gonzalez_delgado_circumnuclear_1996]. After its detection with IRAS, NGC 5953 was followed up with ground-based MIR photometry [cutri_statistical_1985, wright_recent_1988, maiolino_new_1995] and space-based MIR spectrophotometry with ISO [clavel_2.5-11_2000, ramos_almeida_mid-infrared_2007]. The nucleus remained undetected in the first subarcsecond MIR imaging observations [gorjian_10_2004]. A compact nucleus embedded within the star-formation disc with a diameter of ~ 12arcsec is visible in the Spitzer/IRAC 5.8 μm image. In the Spitzer/IRAC 8.0 μm and MIPS 24 μm image, this disc dominates the MIR emission with the brightest location being a compact region at the south-western tip of the disc. Therefore, our corresponding photometry of the unresolved nuclear component is significantly lower than the fluxes published in the literature [engelbracht_metallicity_2008, gallimore_infrared_2010]. The Spitzer/IRS LR staring-mode spectrum is dominated by strong PAH emission and shows a red spectral slope in νFν-space (see also [buchanan_spitzer_2006, wu_spitzer/irs_2009, gallimore_infrared_2010]. Thus, the arcsecond-scale MIR SED is completely star-formation dominated. The nuclear region of NGC 5953 was observed with T-ReCS in the broad N filter in 2004 [videla_nuclear_2013]). In the image, an extended nucleus is faintly visible (S/N~ 1), surrounded by a ring-like structure corresponding to the star-formation disc. Therefore, we use a measurement of the unresolved central component to determine an upper limit on the nuclear flux, which makes up only ~ 14% of the flux seen in the arcsecond-scale MIR SED as probed by Spitzer. This nuclear value is presumably still affected by star formation. On the other hand, the AGN-indicative [Ne V] was detected in the IRS spectrum (e.g. [gallimore_infrared_2010]).

Images

Optical image (DSS, red filter). Displayed are the central 4 arcmin with North being up and East to the left. The colour scaling is linear with white corresponding to the median background (BG) and black to the 0.01% pixels with the highest intensity.

Spitzer MIR images. Displayed are the inner 40 arcsec with North being up and East to the left. The colour scaling is logarithmic with white corresponding to median BG and black to the 0.1% pixels with the highest intensity. The label in the bottom left states instrument and central wavelength of the filter in micron (I: IRAC, M: MIPS).

Subarcsecond-resolution MIR images sorted by increasing filter central wavelength. Displayed are the inner 4 arcsec with North being up and East to the left. The colour scaling is logarithmic with white corresponding to median BG and black to the 75% of the highest intensity of all images in units of sig_bg. The inset image (where present; either bottom or top right) shows the central arcsecond of the PSF from the calibrator star, scaled to match the science target. The labels in the bottom left state instrument and filter names (C: COMICS, M: Michelle, T: T-ReCS, V: VISIR).

SEDs

MIR SED. The description of the symbols in all the SED plots (where present) is the following: Grey crosses and solid lines mark the Spitzer/IRAC, MIPS and IRS data. The colour coding of the other symbols is as follows: green for COMICS, magenta for Michelle, blue for T-ReCS and red for VISIR data. Darker-coloured solid lines mark spectra of the corresponding instrument. The black filled circles mark the nuclear 12 and 18 micron continuum emission estimate from the data (where present). The ticks on the top axis mark positions of common MIR emission lines, while the light grey horizontal bars mark wavelength ranges affected by the silicate 10 and 18 micron features.

Photometry details and reduced FITS files

ObjectRA
[deg]		Dec
[deg]		FilterImageInfoλ_c
[um]		HWHM
[um]		InstrPix. size
[arcsec/pix]		T_exp
[s]		ModeChop Throw
[arcsec]		Chop Angle
[deg]		Rot
[deg]		Prog IdCal. StarCal. DateDate Obs.Factor
[mJy/ct]		Err. Factor
[mJy/ct]		Cal. Flux
[mJy]		Upper Lim. Gauss?F_Gauss
[mJy]		E(F_Gauss)
[mJy]		Upper Lim. PSF?F_PSF
[mJy]		E(F_PSF)
[mJy]		Cal. Maj.
[arcsec]		Cal. Min.
[arcsec]		Cal. PA.
[deg]		Maj. Ax
[arcsec]		Min. Ax
[arcsec]		Pos. Ang.
[deg]
NGC 5953233.63500015.193889N[Details]10.362.64TRECS0.09717.0PARA10.0-90.00.0GS-2004A-Q-14HD1231392004-05-03T04:48:00Z2004-05-03T04:46:34Z0.009240.0001153862.0True18.2N/ATrue12.2N/A0.40.37132.0N/AN/AN/A