IMF - PDF document

近赤外広視野観測から探る褐色矮星・ 惑星質量天体とIMF    Salpeter’s law  Increase monotonously NIR Deep Wide Survey of Very Young  Scalo’s law Kroupa Miller-Scalo  Peark around 0.3Mo Low-mass Objects Scalo  But, data incompleteness  Kroupa’s law Brown Dwarf Brown Dwarf Investigation of the Initial Mass Salpeter Planetary- Planetary-  Peak around 0.1 Mo? Function at Very Low-Mass Side Mass Object Mass Object  But, data incompleteness  →massive  Salpeter (1955) logM 1 2 Star Planet Planet Star Brown Dwarf Brown Dwarf  M dwarf M dwarf T dwarf T dwarf  L dwarf Jupiter Sun Jupiter Sun L dwarf Luminosity 質 Star 量 ( 木 The track of Burrows et al. (1997) 1 -4 Brown Dwarf 星 質 １ 光度 (L/Lo) Young BD and 量 10 - PMOs in Perseus 2 ) Planetary-Mass Object Oasa et al. in prep. -8 12 年 10m/s Pleiades 10 - 0.01 ４ Forming PMOs are brighter 4 th order 1 Field 100 0.01 年齢 1Myr 10Myr 100Myr 1Gyr 10Gyr SFR Sun 0.26pc (5.5’) age 1Myr 軌道半径 (AU) 10Myr 10 - 6 7 1

IMF Massive SFR OriB IMF – Massive SFRs Orion, NGC3603 - Brown Planetary Dwarf Mass Low-Mass Object Star Brown Dwarf Low-Mass Star    16 18 IMF –Intermediate mass SFRs Serpens- IMF Group1 - Massive N Dust clump SFR E Cluster A without CO gas S106- Dust clump Planetary- Mass with CO gas Object Group2 Brown Dwarf Low-  Mass Log[N/logMo] Cluster B Star  Group3 Log[M/Mo] -2 -1 0 Spitzer/IRAC 19 21 2

IMF – Intermediate mass SFR IMF – low mass SFRs Ophiuchi- RCrA & NGC1333- N/Mo Planetary- Brown Mass Objects 5 ’ Brown 0.3Myr Dwarfs DwarfsLow-Mass Low-Mass Stars Clump MF Stars Log[N/logMo] Planetary- Mass Objects Planetary- Mass Objects 1Myr Brown Dwarfs Low-Mass  Stars  Log[M/Mo] 37 38 Q: Substellar-mass objects form everywhere? IMF – Other Clusters & Field -   2MASS Image of NGC7538 11.0´ × 11.0´ LMC IMF  Carlson et al. (2012)  field in M31 using  Carlson et al. 2012 39 40 3

Summary     Open Questions  Is the lower mass objects increasing also in the other regions?  What key physical processes govern the formation of BDs and PMOs?  Is the process same as “star” or “planet”?  The lower end of IMF would be variable. What determines it?  Over a range of mass, metallicity, stellar density, and environment 41 4