skip to main content

Title: SPIRAL ARMS IN THE DISK OF HD 142527 FROM CO EMISSION LINES WITH ALMA

In view of both the size of its gap and the previously reported asymmetries and near-infrared spiral arms, the transition disk of the Herbig Fe star HD 142527 constitutes a remarkable case study. This paper focuses on the morphology of the outer disk through ALMA observations of {sup 12}CO J = 2-1, {sup 12}CO J = 3-2, and {sup 13}CO J = 2-1. Both {sup 12}CO J = 2-1 and {sup 12}CO J = 3-2 show spiral features of different sizes. The innermost spiral arm (S1) is a radio counterpart of the first near-infrared spiral observed by Fukagawa, but it is shifted radially outward. However, the most conspicuous CO spiral arm (S2) lies at the outskirts of the disk and has not been detected before. It corresponds to a cold density structure, with both brightness and excitation temperatures of order 13±2 K and conspicuous in the {sup 12}CO J = 2-1 peak-intensity map, but faint in {sup 12}CO J = 3-2. There is also a faint counterarm (S3), at a point-symmetric location of S2 with respect to the star. These three spirals are modeled separately with two different formulae that approximate the loci of density maxima in acoustic waves duemore » to embedded planets. S1 could be fit relatively well with these formulae, compared to S2 and S3. Alternative scenarios such as gravitational instability or external tidal interaction are discussed. The impact of channelization on spectrally and spatially resolved peak intensity maps is also briefly addressed.« less
Authors:
; ; ;  [1] ;  [2]
  1. Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile)
  2. UMI-FCA, CNRS/INSU, France (UMI 3386) and Departamento de Astronomía, Universidad de Chile, Santiago (Chile)
Publication Date:
OSTI Identifier:
22365907
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 785; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; ASYMMETRY; BRIGHTNESS; CARBON MONOXIDE; COMPARATIVE EVALUATIONS; DENSITY; EXCITATION; GRAVITATIONAL INSTABILITY; HERBIG-HARO OBJECTS; MORPHOLOGY; NEAR INFRARED RADIATION; PLANETS; PROTOPLANETS; SOUND WAVES; STARS