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<p><span class="inline-formula">Δ³</span>-carene is a prominent monoterpene in the atmosphere, contributing significantly to secondary organic aerosol (SOA) formation. However, knowledge about <span class="inline-formula">Δ³</span>-carene oxidation pathways, particularly regarding their ability to form highly oxygenated organic molecules (HOMs), is still limited. In this study, we present HOM measurements during <span class="inline-formula">Δ³</span>-carene ozonolysis under various conditions in two simulation chambers. We identified numerous HOMs (monomers: C<span class="inline-formula">₇₋₁₀</span>H<span class="inline-formula">₁₀₋₁₈</span>O<span class="inline-formula">₆₋₁₄</span>; dimers: C<span class="inline-formula">₁₇₋₂₀</span>H<span class="inline-formula">₂₄₋₃₄</span>O<span class="inline-formula">₆₋₁₈</span>) using a chemical ionization mass spectrometer (CIMS). <span class="inline-formula">Δ³</span>-carene ozonolysis yielded higher HOM concentrations than <span class="inline-formula"><i>α</i></span>-pinene, with a distinct distribution, indicating differences in formation pathways. All HOM signals decreased considerably at lower temperatures, reducing the estimated molar HOM yield from <span class="inline-formula">∼</span> 3 % at 20 °C to <span class="inline-formula">∼</span> 0.5 % at 0 °C. Interestingly, the temperature change altered the HOM distribution, increasing the observed dimer-to-monomer ratios from roughly 0.8 at 20 °C to 1.5 at 0 °C. HOM monomers with six or seven O atoms condensed more efficiently onto particles at colder temperatures, while monomers with nine or more O atoms and all dimers condensed irreversibly even at 20 °C. Using the gas- and particle-phase chemistry kinetic multilayer model ADCHAM, we were also able to reproduce the experimentally observed HOM composition, yields, and temperature dependence.</p>