مناسك حج - مكارم شيرازى، ناصر - الصفحة ١٦٠ - Hajj al -Tamattu
Article ٢٦٢- Although staying in Arafat is obligatory in all the time that has been mentioned before and renouncing it is a sin, but it is not one of essentials of Hajj, and the pillar is staying for a while in there, it means that if a person stays a part of the time from noon until sunset in Arafat, then his/ her Hajj is correct, but if he/ she renounces all the time then the Hajj is invalidated.
Article ٢٦٣- It is obligatory for a person who has not been successful of completing Wuquf in Arafat from noon until sunset to stay some time in the night of Eid in that place; therefore, if a pilgrim reaches Arafat when people have left there, he/ she stays a part of the night in there on the condition that he/ she can reach Mashar al- Haraam before the dawn of the day of Eid and this is called" Emergency Wuquf of Arafat".
And if this person couldnt stay a part of night in Arafat, it is enough for him/ her to perceive Wuquf a part of Wuquf in Mashar al- Haraam, which will be mentioned later, and his/ her Hajj is correct in this way.