3D dust properties of supernova remnant S147 Bingqiu Chen ( 陈丙秋, bchen@pku.edu.cn), Peking University Xiaowei Liu, Juanjuan Ren, Haibo Yuan, Maosheng Xiang, et al. 2016.07.26 Chengdu
Outline Introduction Radial velocity field Data and method Results Distance Mass Discussion Other tracers The extinction law DIBs Conclusion Future work
SNR S147 Simeis 147, Sh2-240, SNR G180.0-01.7 Location: α=05h39m00s, δ=+27 50'00 Size: ~200 arcmin (76pc) Distance: 1.3 kpc Age: ~30,000 yr Radio: Large faint shell Optical: Wispy ring. X-ray: Possible detection. Point sources: Pulsar within boundary, with faint wind nebula. Extinction: Av=0.7 mag (Fesen, Blair & Kirshner 1985, d=0.8 kpc)
(IPHAS Hα) (DSS red) (6cm) N E (11cm) (33 GHz) (41GHz)
LAMOST observations towards S147 LAMOST DR2: 50 plates green: 16 plates distance from S147 center 3.55 deg; 10B + 6M plates ; pilot: 9 plates; DR1: 7 plates blue: 34 plates distance from S147 center between 3.55 and 4.54 deg; 5V + 26B + 16M+ 3F plates ; pilot: 28 plates; DR1: 18 plates; DR2: 4 plates
The radial velocity field of S147 Ren et al. in prep., Based on the Ha emission line from spectra of: 1) sky fiber (filled circles) 2) stars with parameters and subtracted from templates (filled squares) 3) stars with low SNR (filled triangles)
The molecular cloud associated with S147? Phillips et al. 1981: Detection of low-velocity interstellar CO absorption features in the UV spectrum toward HD36665 (d=0.9kpc) Huang et al. 1986: A weak cloud with peak velocity of 4km/s. Whether the cloud is associated with the SNR remains unknown, But it probably does lie in front of the SNR, because a dust line can be barely seen against the optical filaments in the line of sight.
The molecular cloud associated with S147? Sallmen et al. 2004: obtained high-resolution spectra of the interstellar NaI and Ca II absorption lines observed towards 3 stars with distances raging from 360 1380 pc in sight-lines towards the S47 SNR. The two most distant stars, HD 36665 (d = 880 pc) and HD 37318 (d = 1380 pc), lie beyond the SNR gas and possess complex absorption profiles in which components have been detected over a velocity range of 65 to +80 km/s. The foreground star, HD 37367, exhibits none of these intermediate velocity components. Jeong et al. 2012: found some molecular clouds at velocities from 14 to +5 km/s. Although we detected molecular clouds near the SNR, none of them show correlated features with the remnant.
Introduction This work: we are going to search for the possible associated dust (molecular) cloud of S147 from the 3D dust extinction mapping and study its properties (if yes). The data we are using: XSTPS-GAC photometric sample LSS-GAC spectroscopic sample
S147 viewed by XSTPS-GAC XSTPS-GAC r-band image FoV: 1.94 x 1.94 integration time: 90 s DSS
Extinction and distances from photometric data Chen et al. 2014 We combine XSTPS-GAC (g, r, i) data with those of 2MASS and WISE (J, H,Ks, W1, W2) and then applied the SED fitting to derive the best-fit extinction and distance information of stars. Mr=f(g-i)+f([Fe/H]) g-r, r-i, i-j, J-H,H-Ks, Ks-W1, W1-W2
The value-added catalogue of LSS-GAC DR2 Extinction: star pair method (Yuan et al. 2015) Distance:M_K from KPCA method (Xiang et al. submitted) DIB: star pair method (Yuan et al. in prep.) Xiang et al. in prep.
Comparisons between the two samples Ar (spec.) = 0.1 + Ar (phot.) The differences are possibly caused by the spatial variations of the extinction law as well as by the uncertainties of the photometric method which tends to underestimate the true values of reddening d(spec.)=1.2d(phot.) The differences are mainly due to the sub-giant/f turnoff stars which have Teff > 5000K.
The extinction distribution for different depth We parameterize Ar(d) as a piecewise linear function in the distance: with separations between adjacent points of 0.1 kpc.
Dust distribution at different distances
3D structure of the dust in the vicinity of S147
The 3D distribution of dust towards S147 Dust distribution for 1.0 < d < 1.2 kpc Dust distribution for 0.8 < d < 1.0 kpc (R) 1.4 < d < 1.2 kpc (G) 1.2 < d < 1.4 kpc (B) 2D dust distribution from Froebrich et al. (2003)
Example lines of sight
S147 dust cloud The amount of reddening for pixels in each selected field (left panel) and distance bin. The main molecular clouds appear prominently at a distance of about 1.05 and 1.15 kpc
Distance We fit the distance-extinction relation by: MW background dust: Chen et al. 1998 S147 dust: d0=1.11 kpc ΔAr=0.25 mag Δd= 0.07kpc d0=1.37 kpc ΔAr=0.28 mag Δd= 0.01kpc
Mass Mass calculated similar as in Lombardi et al. 2011: μ=1.37 (Lombardi et al. 2011) & β=2.4e21 (Chen et al. 2015) M = 75,987 Msun
SNR interacted with the molecular cloud CO 6cm Ar(1.1kpc) this work X-ray Halpha Ar(1.1kpc) Green et al. 2015
The extinction law toward S147 Yuan2013 R(r-i): 0.60 0.60 R(i-J): 1.08 0.99 R(J-H): 0.38 0.26 R(H-Ks): 0.16 0.16
DIBs EW(5780)=0.13+0.53E(B-V) EW(5780)=0.61E(B-V) EW(5796)=0.06+0.16E(B-V) Linear fit Yuan+2012 EW(6284)=0.26+1.32E(B-V) EW(6284)=1.26E(B-V) Target/Template spectra
Conclusion We isolate the dust structure of S147 using the 3D extinction mapping, revealing a large previously unrecognized dust structure. We determine the distance of S147 as photometric distance of d=1.1 kpc and spectroscopic distance of d=1.3 kpc; We obtain the mass of the cloud as M=75,987 Msun; The dust structure are associated to all other tracers of S147. The morphology shows complicated SNR interactions with molecular clouds. The extinction law and DIB properties in the S147 dust cloud show special properties of cloud influenced by the Supernovae.
Future work Other SNRs: Bin Yu s report Thank you!