682 research outputs found
Infinite dimensional Lie algebras in 4D conformal quantum field theory
The concept of global conformal invariance (GCI) opens the way of applying
algebraic techniques, developed in the context of 2-dimensional chiral
conformal field theory, to a higher (even) dimensional space-time. In
particular, a system of GCI scalar fields of conformal dimension two gives rise
to a Lie algebra of harmonic bilocal fields, V_m(x,y), where the m span a
finite dimensional real matrix algebra M closed under transposition. The
associative algebra M is irreducible iff its commutant M' coincides with one of
the three real division rings. The Lie algebra of (the modes of) the bilocal
fields is in each case an infinite dimensional Lie algebra: a central extension
of sp(infty,R) corresponding to the field R of reals, of u(infty,infty)
associated to the field C of complex numbers, and of so*(4 infty) related to
the algebra H of quaternions. They give rise to quantum field theory models
with superselection sectors governed by the (global) gauge groups O(N), U(N),
and U(N,H)=Sp(2N), respectively.Comment: 16 pages, with minor improvements as to appear in J. Phys.
Π€Π»Π΅ΠΊΡΠΈΠ±ΠΈΠ»Π½Π°ΡΠ° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΡ ΠΏΡΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ° β Π΄ΠΈΠ°Π³Π½ΠΎΡΡΠΈΡΠ½ΠΈ ΡΠ΅Π·ΡΠ»ΡΠ°ΡΠΈ ΠΈ ΠΏΠΎΠ»Π·ΠΈ
Π¦Π΅Π»ΠΈΡΠ΅ Π½Π° ΡΠ°Π·ΠΈ ΡΡΠ°ΡΠΈΡ ΡΠ° Π΄Π° ΡΠ΅ ΠΏΡΠΎΡΡΠ°Ρ ΠΈ ΠΈΠ·Π»ΠΎΠΆΠ°Ρ Π²ΡΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈΡΠ΅ ΠΈ ΠΏΡΠ΅Π΄ΠΈΠΌΡΡΠ²Π°ΡΠ° Π½Π° ΡΠ»Π΅ΠΊΡΠΈΠ±ΠΈΠ»Π½Π°ΡΠ° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΡ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ° Π² ΠΎΡΠΎΡΠΈΠ½ΠΎΠ»Π°ΡΠΈΠ½Π³ΠΎΠ»ΠΎΠ³ΠΈΡΠ½Π°ΡΠ° ΠΏΡΠ°ΠΊΡΠΈΠΊΠ°.ΠΡΡΡ
Ρ 191 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ Ρ ΡΠ°Π·Π»ΠΈΡΠ½ΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ° Π·Π° ΠΏΠ΅ΡΠΈΠΎΠ΄Π° ΡΠ½ΠΈ 2008 Π΄ΠΎ ΡΠ½ΠΈ 2011 Π³., Π² Π£ΠΠ-ΠΊΠ»ΠΈΠ½ΠΈΠΊΠ° Π½Π° Π£ΠΠΠΠ βΠ‘Π². ΠΠ΅ΠΎΡΠ³ΠΈβ β ΠΠ»ΠΎΠ²Π΄ΠΈΠ² ΠΈΠ·Π²ΡΡΡΠΈΡ
ΠΌΠ΅ Π² Π°ΠΌΠ±ΡΠ»Π°ΡΠΎΡΠ΅Π½ ΠΏΠΎΡΡΠ΄ΡΠΊ ΠΈΠ»ΠΈ ΠΏΡΠΈ Π»Π΅Π³Π»ΠΎΡΠΎ Π½Π° Π±ΠΎΠ»Π½ΠΈΡ ΡΠΈΠ±ΡΠΎΠ½Π°Π·ΠΎ-Π΅ΠΏΠΈΡΠ°ΡΠΈΠ½Π³ΠΎΠ»Π°ΡΠΈΠ½Π³ΠΎΡΠΊΠΎΠΏΠΈΠΈ. ΠΠ·ΡΠ»Π΅Π΄Π²Π°Π½Π΅ΡΠΎ ΠΈΠ·Π²ΡΡΡΠ²Π°Ρ
ΠΌΠ΅ ΠΏΠΎΠ΄ ΠΌΠ΅ΡΡΠ½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΡ, Ρ ΡΡΠ°Π½ΡΠ½Π°Π·Π°Π»Π΅Π½ Π΄ΠΎΡΡΡΠΏ ΠΊΠ°ΡΠΎ ΠΈΠ·ΠΏΠΎΠ»Π·Π²Π°Ρ
ΠΌΠ΅ Π½Π°Π·Π°Π»Π½ΠΈ Π΄Π΅ΠΊΠΎΠ½Π³Π΅ΡΡΠ°Π½ΡΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΈΡ Π·Π° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΡΡΠ° Π½Π° Π³ΠΎΡΠ½ΠΈΡ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π΅Π½ ΠΏΡΡ Π±ΡΡ
Π° β Π΄ΠΈΡΡΠΎΠ½ΠΈΡ, Π΄ΠΈΡΡΠ°Π³ΠΈΡ ΠΈ Π·Π°ΡΡΡΠ΄Π½Π΅Π½ΠΎ Π½ΠΎΡΠ½ΠΎ Π΄ΠΈΡΠ°Π½Π΅ ΠΏΡΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ, Π½Π° ΠΊΠΎΠΈΡΠΎ ΠΊΠ»Π°ΡΠΈΡΠ΅ΡΠΊΠ°ΡΠ° ΠΎΠ³Π»Π΅Π΄Π°Π»Π½Π° Π΅ΠΏΠΈΡΠ°ΡΠΈΠ½Π³ΠΎ ΠΈ Π»Π°ΡΠΈΠ½Π³ΠΎΡΠΊΠΎΠΏΠΈΡ Π½Π΅ Π΄Π°Π²Π°Ρ
Π° ΠΈΠ·ΡΠ΅ΡΠΏΠ°ΡΠ΅Π»Π½Π° ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ Π·Π° ΠΏΠΎΡΡΠ°Π²ΡΠ½Π΅ΡΠΎ Π½Π° Π΄ΠΈΠ°Π³Π½ΠΎΠ·Π°ΡΠ°, ΠΊΠ°ΠΊΡΠΎ ΠΈ ΠΏΡΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ Ρ ΡΠ΅ΠΆΠΊΠΈ ΠΏΡΠΈΠ΄ΡΡΠΆΠ°Π²Π°ΡΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ, ΠΏΡΠΈ ΠΊΠΎΠΈΡΠΎ ΠΈΠ·Π²ΡΡΡΠ²Π°Π½Π΅ΡΠΎ Π½Π° Π΄ΠΈΡΠ΅ΠΊΡΠ½Π° Π»Π°ΡΠΈΠ½Π³ΠΎΡΠΊΠΎΠΏΠΈΡ ΠΏΠΎΠ΄ ΠΎΠ±ΡΠ° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΡ Π±Π΅ΡΠ΅ ΠΏΡΠΎΡΠΈΠ²ΠΎΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ Π·Π°ΡΠ°Π΄ΠΈ ΡΠ΅ΠΆΠΊΠΈ ΠΏΡΠΈΠ΄ΡΡΠΆΠ°Π²Π°ΡΠΈ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ ΠΈ ΠΏΠΎΠ²ΠΈΡΠ΅Π½ ΡΠΈΡΠΊ ΠΎΡ ΠΆΠΈΠ²ΠΎΡΠΎΠ·Π°ΡΡΡΠ°ΡΠ°Π²Π°ΡΠΈ ΠΈΠ½ΡΠΈΠ΄Π΅Π½ΡΠΈ ΠΏΠΎ Π²ΡΠ΅ΠΌΠ΅ Π½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΡΡΠ°. Π Π°Π±ΠΎΡΠ΅Ρ
ΠΌΠ΅ Ρ ΡΠΈΠ±ΡΠΎΠ±ΡΠΎΠ½Ρ
ΠΎΡΠΊΠΎΠΏ Olympus Ρ Π²ΡΠ½ΡΠ΅Π½ Π΄ΠΈΠ°ΠΌΠ΅ΡΡΡ 2,2 ΠΌΠΌ ΠΈ ΡΠ°Π±ΠΎΡΠ΅Π½ ΠΊΠ°Π½Π°Π» 1,2 ΠΌΠΌ ΡΠ½Π°Π±Π΄Π΅Π½ Ρ ΡΠΈΠ±ΡΠΎΡΠΈΠΏΠΊΠ°, ΠΊΠΎΠΉΡΠΎ ΠΈΠ·ΠΏΠΎΠ»Π·Π²Π°Ρ
ΠΌΠ΅ Π·Π° ΠΎΠ³Π»Π΅Π΄ Π½Π° Π΄Π΅ΡΠ° Π²ΠΊΠ»ΡΡΠΈΡΠ΅Π»Π½ΠΎ ΠΈ Π½ΠΎΠ²ΠΎΡΠΎΠ΄Π΅Π½ΠΈ. ΠΠ° Π²ΡΠ·ΡΠ°ΡΡΠ½ΠΈ ΠΈΠ·ΠΏΠΎΠ»Π·ΡΠ²Π°Ρ
ΠΌΠ΅ ΡΠΈΠ±ΡΠΎΠ±ΡΠΎΠ½Ρ
ΠΎΡΠΊΠΎΠΏ Karl Storz Ρ5,2 ΠΌΠΌ Ρ ΡΠ°Π±ΠΎΡΠ΅Π½ ΠΊΠ°Π½Π°Π» 3,2 ΠΌΠΌ. Π€ΠΈΠ±ΡΠΎΠ΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΡΠ΅ Π°Π΄Π°ΠΏΡΠΈΡΠ°Ρ
ΠΌΠ΅ ΠΊΡΠΌ Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΡΠΊΠ° Π²ΠΈΠ΄Π΅ΠΎΠΊΠ°ΠΌΠ΅ΡΠ° Olympus ΡΠ²ΡΡΠ·Π°Π½Π° Ρ Π²ΠΈΠ΄Π΅ΠΎΠΌΠΎΠ½ΠΈΡΠΎΡ ΠΈ Π·Π°ΠΏΠΈΡΠ²Π°ΡΠΎ DVD Π·Π° ΡΠΎΡΠΎΠ΄ΠΎΠΊΡΠΌΠ΅Π½ΡΠ°ΡΠΈΡ. ΠΡΠ΅Π· ΠΏΠΎΡΠ»Π΅Π΄Π½Π°ΡΠ° Π³ΠΎΠ΄ΠΈΠ½Π° ΠΎΡ Π½Π°ΡΠ΅ΡΠΎ ΠΏΡΠΎΡΡΠ²Π°Π½Π΅ ΠΈΠ·ΡΠ»Π΅Π΄Π²Π°Π½ΠΈΡΡΠ° ΠΈΠ·Π²ΡΡΡΠ²Π°Ρ
ΠΌΠ΅ ΡΡΡ XYON ΡΠ»Π΅ΠΊΡΠΈΠ±ΠΈΠ»Π΅Π½ Π½Π°Π·ΠΎΡΠ°ΡΠΈΠ½Π³ΠΎΠ»Π°ΡΠΈΠ½Π³ΠΎΡΠΊΠΎΠΏ Ρ Π²ΠΈΠ΄Π΅ΠΎΠΌΠΎΠ½ΠΈΡΠΎΡ.Π Π΅Π·ΡΠ»ΡΠ°ΡΠΈ: ΠΠ° 191 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ , ΠΎΡ ΠΊΠΎΠΈΡΠΎ 151 ΠΌΡΠΆΠ΅ (80,29%) ΠΈ 40 ΠΆΠ΅Π½ΠΈ (20.8%), Π½Π° ΡΡΠ΅Π΄Π½Π° Π²ΡΠ·ΡΠ°ΡΡ 48.4 Π³ΠΎΠ΄ΠΈΠ½ΠΈ ΠΈΠ·Π²ΡΡΡΠ²Π°Ρ
ΠΌΠ΅ ΡΠΈΠ±ΡΠΎΠ΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΠΈ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ°. ΠΠ°ΠΉ-ΡΠ΅ΡΡΠΈΡΠ΅ Π·Π°Π±ΠΎΠ»ΡΠ²Π°Π½ΠΈΡ, ΠΊΠΎΠΈΡΠΎ ΠΎΡΠΊΡΠΈΡ
ΠΌΠ΅ ΠΏΡΠΈ ΡΠ΅ΡΠΈΡΡΠ° ΠΎΡ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ Π±ΡΡ
Π° ΡΠ»Π΅Π΄Π½ΠΈΡΠ΅: Π±Π΅Π½ΠΈΠ³Π½Π΅Π½ΠΈ Π°Π±Π½ΠΎΡΠΌΠ°Π»ΠΈΡΠ΅ΡΠΈ Π½Π° Π»Π°ΡΠΈΠ½ΠΊΡΠ° 51 (26,7%), ΠΊΠ°ΡΡΠΈΠ½ΠΎΠΌΠΈ Π½Π° Π»Π°ΡΠΈΠ½ΠΊΡΠ° 24 (12.3%), ΠΊΠ°ΡΡΠΈΠ½ΠΎΠΌΠΈ Π½Π° Ρ
ΠΈΠΏΠΎΡΠ°ΡΠΈΠ½ΠΊΡΠ° 18 (9,2%), ΠΊΠ°ΡΡΠΈΠ½ΠΎΠΌΠΈ Π½Π° Π΅ΠΏΠΈΡΠ°ΡΠΈΠ½ΠΊΡΠ° 14 (7,2%), ΠΏΠ°ΡΠ΅Π·ΠΈ Π½Π° Π³Π»Π°ΡΠ½ΠΈΡΠ΅ Π²ΡΡΠ·ΠΊΠΈ 26 (13,4%), Π΅Π΄Π΅ΠΌ Π½Π° Π»Π°ΡΠΈΠ½ΠΊΡΠ° 8 (4,1%), Π½Π°Π·Π°Π»Π½Π° ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡ 28 (14,4%) Π²ΡΠΎΠ΄Π΅Π½ΠΈ Π°Π½ΠΎΠΌΠ°Π»ΠΈΠΈ 5 (2,5%), ΡΠΌΡΡΠ΅Π½ΠΈΡ Π² Π°ΠΊΡΠ° Π½Π° Π³ΡΠ»ΡΠ°Π½Π΅ΡΠΎ ΡΠ»Π΅Π΄ ΡΠ°ΡΡΠΈΡΠ½ΠΈ Ρ
ΠΎΡΠΈΠ·ΠΎΠ½ΡΠ°Π»Π½ΠΈ ΡΠ΅Π·Π΅ΠΊΡΠΈΠΈ Π½Π° Π»Π°ΡΠΈΠ½ΠΊΡΠ° ΠΏΠΎ ΠΏΠΎΠ²ΠΎΠ΄ ΠΊΠ°ΡΡΠΈΠ½ΠΎΠΌ 8 (4,1%), ΡΡΠΆΠ΄ΠΈ ΡΠ΅Π»Π° Π² Π½ΠΎΡΠ° Π½Π°Π·ΠΎ,Ρ
ΠΈΠΏΠΎΡΠ°ΡΠΈΠ½ΠΊΡΠ° ΠΈ Ρ
ΡΠ°Π½ΠΎΠΏΡΠΎΠ²ΠΎΠ΄Π° 6 (3,09%).ΠΠ°ΠΊΠ»ΡΡΠ΅Π½ΠΈΠ΅: Π€Π»Π΅ΠΊΡΠΈΠ±ΠΈΠ»Π½Π°ΡΠ° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΠΈΡ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ° Π΅ ΠΈΠ·ΠΊΠ»ΡΡΠΈΡΠ΅Π»Π½ΠΎ Π΅ΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎ ΠΈΠ½ΡΡΡΡΠΌΠ΅Π½ΡΠ°Π»Π½ΠΎ ΠΈΠ·ΡΠ»Π΅Π΄Π²Π°Π½Π΅ ΠΏΡΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΈ Ρ ΡΠ°Π·Π»ΠΈΡΠ½Π° ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡ Π½Π° Π³ΠΎΡΠ½ΠΈΡΠ΅ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π½ΠΈ ΠΏΡΡΠΈΡΠ°. ΠΡΠΎΡΠ΅Π΄ΡΡΠ°ΡΠ° Π΅ Π»Π΅ΡΠ½ΠΎ ΠΈΠ·ΠΏΡΠ»Π½ΠΈΠΌΠ° ΠΏΠΎΠ΄ Π»ΠΎΠΊΠ°Π»Π½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΡ Π² Π°ΠΌΠ±ΡΠ»Π°ΡΠΎΡΠ½ΠΈ ΡΡΠ»ΠΎΠ²ΠΈΡ, ΠΊΠ°ΠΊΡΠΎ ΠΈ ΠΏΡΠΈ Π»Π΅Π³Π»ΠΎΡΠΎ Π½Π° Π±ΠΎΠ»Π½ΠΈΡ. ΠΡΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈΡΠ΅ Π·Π° Π²Π·ΠΈΠΌΠ°Π½Π΅ Π½Π° Π±ΠΈΠΎΠΏΡΠΈΠΈ ΠΏΠΎΠ΄ Π»ΠΎΠΊΠ°Π»Π½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΡ ΠΏΠΎ Π²ΡΠ΅ΠΌΠ΅ Π½Π° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΡΠΊΠΈΡ ΠΎΠ³Π»Π΅Π΄ Ρ ΠΏΡΠ°Π²ΠΈ ΡΠ΅Π½Π΅Π½ ΠΏΡΠΈΠ΄Π°ΡΡΠΊ ΠΊΠ°ΠΊΡΠΎ Π² ΠΎΠ±ΡΠ°Π·Π½ΠΎΡΠΎ ΠΈΠ·ΡΠ»Π΅Π΄Π²Π°Π½Π΅ Π½Π° Π³ΠΎΡΠ½ΠΈΡ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π΅Π½ ΠΏΡΡ, ΡΠ°ΠΊΠ° ΠΈ Π² Ρ
ΠΈΡΡΠΎΠ»ΠΎΠ³ΠΈΡΠ½Π°ΡΠ° Π²Π΅ΡΠΈΡΠΈΠΊΠ°ΡΠΈΡ Π½Π° ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡΠ½ΠΈ ΠΏΡΠΎΡΠ΅ΡΠΈ Π½Π° Π³ΠΎΡΠ½ΠΈΡΡ Π΄ΠΈΡ
Π°ΡΠ΅Π»Π΅Π½ ΠΏΡΡ. Π’Π΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΡΠ½ΠΈΡΡ Π½Π°ΠΏΡΠ΅Π΄ΡΠΊ Π² ΠΎΠ±Π»Π°ΡΡΡΠ° Π΄Π°Π²Π° Π²ΡΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡ Π·Π° ΡΡΠ·Π΄Π°Π²Π°Π½Π΅ Π½Π° Π΅Π½Π΄ΠΎΡΠΊΠΎΠΏΡΠΊΠ° Π°ΠΏΠ°ΡΠ°ΡΡΡΠ°, ΠΏΡΠΈΠ»ΠΎΠΆΠΈΠΌΠ° Π·Π° ΠΈΠ·ΡΠ»Π΅Π΄Π²Π°Π½ΠΈΡ Π΄ΠΎΡΠΈ ΠΏΡΠΈ Π½ΠΎΠ²ΠΎΡΠΎΠ΄Π΅Π½ΠΈ
Physical properties, starspot activity, orbital obliquity, and transmission spectrum of the Qatar-2 planetary system from multi-colour photometry
We present seventeen high-precision light curves of five transits of the
planet Qatar-2b, obtained from four defocussed 2m-class telescopes. Three of
the transits were observed simultaneously in the SDSS griz passbands using the
seven-beam GROND imager on the MPG/ESO 2.2-m telescope. A fourth was observed
simultaneously in Gunn grz using the CAHA 2.2-m telescope with BUSCA, and in r
using the Cassini 1.52-m telescope. Every light curve shows small anomalies due
to the passage of the planetary shadow over a cool spot on the surface of the
host star. We fit the light curves with the prism+gemc model to obtain the
photometric parameters of the system and the position, size and contrast of
each spot. We use these photometric parameters and published spectroscopic
measurements to obtain the physical properties of the system to high precision,
finding a larger radius and lower density for both star and planet than
previously thought. By tracking the change in position of one starspot between
two transit observations we measure the orbital obliquity of Qatar-2 b to be
4.3 \pm 4.5 degree, strongly indicating an alignment of the stellar spin with
the orbit of the planet. We calculate the rotation period and velocity of the
cool host star to be 11.4 \pm 0.5 d and 3.28 \pm 0.13 km/s at a colatitude of
74 degree. We assemble the planet's transmission spectrum over the 386-976 nm
wavelength range and search for variations of the measured radius of Qatar-2 b
as a function of wavelength. Our analysis highlights a possible H2/He Rayleigh
scattering in the blue.Comment: 20 pages, 14 figures, to appear in Monthly Notices of the Royal
Astronomical Societ
Jacobi Identity for Vertex Algebras in Higher Dimensions
Vertex algebras in higher dimensions provide an algebraic framework for
investigating axiomatic quantum field theory with global conformal invariance.
We develop further the theory of such vertex algebras by introducing formal
calculus techniques and investigating the notion of polylocal fields. We derive
a Jacobi identity which together with the vacuum axiom can be taken as an
equivalent definition of vertex algebra.Comment: 35 pages, references adde
Simultaneous follow-up of planetary transits: revised physical properties for the planetary systems HAT-P-16 and WASP-21
Context. By now more than 300 planets transiting their host star have been
found, and much effort is being put into measuring the properties of each
system. Light curves of planetary transits often contain deviations from a
simple transit shape, and it is generally difficult to differentiate between
anomalies of astrophysical nature (e.g. starspots) and correlated noise due to
instrumental or atmospheric effects. Our solution is to observe transit events
simultaneously with two telescopes located at different observatories. Aims.
Using this observational strategy, we look for anomalies in the light curves of
two transiting planetary systems and accurately estimate their physical
parameters. Methods. We present the first photometric follow-up of the
transiting planet HAT-P-16 b, and new photometric observations of WASP-21 b,
obtained simultaneously with two medium-class telescopes located in different
countries, using the telescope defocussing technique. We modeled these and
other published data in order to estimate the physical parameters of the two
planetary systems. Results. The simultaneous observations did not highlight
particular features in the light curves, which is consistent with the low
activity levels of the two stars. For HAT-P-16, we calculated a new ephemeris
and found that the planet is 1.3 \sigma colder and smaller (Rb = 1.190 \pm
0.037 RJup) than the initial estimates, suggesting the presence of a massive
core. Our physical parameters for this system point towards a younger age than
previously thought. The results obtained for WASP-21 reveal lower values for
the mass and the density of the planet (by 1.0 \sigma and 1.4 \sigma
respectively) with respect to those found in the discovery paper, in agreement
with a subsequent study. We found no evidence of any transit timing variations
in either system.Comment: 8 pages, 6 figures, accepted for publication in A&
HATS-5b: A Transiting hot-Saturn from the HATSouth Survey
We report the discovery of HATS-5b, a transiting hot-Saturn orbiting a G type
star, by the HAT-South survey. HATS-5b has a mass of Mp=0.24 Mj, radius of
Rp=0.91 Rj, and transits its host star with a period of P=4.7634d. The radius
of HATS-5b is consistent with both theoretical and empirical models. The host
star has a V band magnitude of 12.6, mass of 0.94 Msun, and radius of 0.87
Rsun. The relatively high scale height of HATS-5b, and the bright,
photometrically quiet host star, make this planet a favourable target for
future transmission spectroscopy follow-up observations. We reexamine the
correlations in radius, equilibrium temperature, and metallicity of the
close-in gas-giants, and find hot Jupiter-mass planets to exhibit the strongest
dependence between radius and equilibrium temperature. We find no significant
dependence in radius and metallicity for the close-in gas-giant population.Comment: 10 pages, submitted to A
- β¦