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We recently reported the first identification of rotational transitions ofmethyl formate (HCOOCH$_{3}$) in the second torsionally excited state towardOrion Kleinmann-Low (KL) observed with the Nobeyama 45 m telescope. Incombination with the identified transitions of methyl formate in the groundstate and the first torsional excited state, it was found that there is adifference in rotational temperature and vibrational temperature, where thelatter is higher. In this study, high spatial resolution analysis by usingAtacama Large Millimeter/Submillimeter Array (ALMA) science verification datawas carried out to verify and understand this difference. Toward the CompactRidge, two different velocity components at 7.3 and 9.1 km s$^{-1}$ wereconfirmed, while a single component at 7.3 km s$^{-1}$ was identified towardsthe Hot Core. The intensity maps in the ground, first, and second torsionalexcited states have quite similar distributions. Using extensive ALMA data, wedetermined the rotational and vibrational temperatures for the Compact Ridgeand Hot Core by the conventional rotation diagram method. The rotationaltemperature and vibrational temperatures agree for the Hot Core and for onecomponent of the Compact Ridge. At the 7.3 km s$^{-1}$ velocity component forthe Compact Ridge, the rotational temperature was found to be higher than thevibrational temperature. This is different from what we obtained from theresults by using the single-dish observation. The difference might be explainedby the beam dilution effect of the single-dish data and/or the smaller numberof observed transitions within the limited range of energy levels ($\leq$30 K)of $E_u$ in the previous study.

ALMA imaging study of methyl formate (HCOOCH$_{3}$) in the torsionally excited states towards Orion KL