Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The size, luminosity and motion of the extreme carbon star IRC+10216 (CW
  Leonis)   Very Large Array observations of the extreme carbon star IRC+10216 at 7 mm
wavelength with 40 milli-arcsecond resolution resolve the object's radio
emission, which forms an almost round uniform disk of 83 milli arcseconds
diameter, corresponding to 11 AU (for an assumed distance of 130 pc). We find a
brightness temperature of 1630 K for the radio photosphere. Since the emission
is optically thick, we can directly estimate IRC+10216's average luminosity,
which is 8600 L(Sun). This value is in excellent agreement with what is
predicted from the period-luminosity relation for carbon-rich Miras. Assuming
an effective temperature of 2750 K for IRC+10216, it implies an optical
photospheric diameter of 3.8 AU. Our precise determination of IRC+10216's
proper motion fits the picture presented by far-ultraviolet and far-infrared
wavelength observations of its interaction region with the interstellar medium
(its "astrosphere"): the star moves roughly in the direction expected from the
morphology of the termination shock and its astrotail structures. Calculation
of its three dimensional velocity and an analysis of the kinematics of its
surrounding interstellar medium (ISM) suggest an appreciable relative velocity
of 42 km s/s, which is about half the value discussed in recent studies. This
suggests a lower (time-averaged) mass loss rate and/or a higher ISM density
than previously assumed.

14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys