Alright I will answer this since we have ruled out the jhana that only leaves the realm of infinite space, infinite consciousness, nothingness, neither perception nor non perception and cessation of feeling and perception
But we need to rule out the realm of nothingness and lower because there still exists desire there while in deep sleep none of even desire exists
“
And further, with the complete transcending of the dimension of the
infinitude of consciousness, (perceiving,) ‘There is nothing,’
Sāriputta entered & remained in the dimension of nothingness. Whatever
qualities there are in the dimension of nothingness—the perception of
the dimension of nothingness, singleness of mind, contact, feeling,
perception, intention, consciousness, desire, decision,
persistence, mindfulness, equanimity, & attention—he ferreted them out
one after another. Known to him they arose, known to him they became
established, known to him they subsided. He discerned, ‘So this is how
these qualities, not having been, come into play. Having been, they
vanish.’ He remained unattracted & unrepelled with regard to those
qualities, independent, detached, released, dissociated, with an
awareness rid of barriers. He discerned that ‘There is a further
escape,’ and pursuing it, he confirmed that ‘There is.’
https://www.dhammatalks.org/suttas/MN/MN111.html
We also need to rule out cessation of perception and feeling since a person of no integrity can't enter that while they can still enter deep sleep
And further, a person of no integrity… enters & remains in the
second jhāna… the third jhāna… the fourth jhāna… the dimension of the
infinitude of space… the dimension of the infinitude of consciousness…
the dimension of nothingness… the dimension of neither perception
nor non-perception. He notices, ‘I have gained the attainment of the
dimension of neither perception nor non-perception, but these other
monks have not gained the attainment of the dimension of neither
perception nor non-perception.’ He exalts himself for the attainment
of the dimension of neither perception nor non-perception and
disparages others. This is the quality of a person of no integrity.
“A person of integrity notices, ‘The Blessed One has spoken of
non-fashioning even with regard to the attainment of the dimension of
neither perception nor non-perception, for by whatever means they
suppose it, it becomes otherwise from that.’ So, giving priority to
non-fashioning, he neither exalts himself for the attainment of the
dimension of neither perception nor non-perception nor disparages
others. This is the quality of a person of integrity.
“A person of integrity, completely transcending the dimension of
neither perception nor non-perception, enters & remains in the
cessation of perception & feeling. When he sees with discernment,
his effluents are ended. This is a monk who does not suppose anything,
does not suppose anywhere, does not suppose in any way.”
That leaves on the realm of neither perception nor non perception as deep sleep which means every single day we enter the realm of neither perception nor non perception without we even realize every single day we do deep samatha meditation without we even realize
https://www.dhammatalks.org/suttas/MN/MN113.html